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CLIOwin 6.5 PCI User`s Manual

1. 0 00 2 0 4 0 6 0 8 0 10 0 12 14 16 ms 18 20 Figure 11 5 The time of sound fly is clearly visible at the beginning roughly 1 3ms This is the value users should input in the Delay Edit Box Thereafter is a short time the device takes to start This is usually short enough to not affect amplitude evaluation but adversely affect distortion measurements At 7 and 8 ms where there are two consequent sinusoid positive peak a level increase Is clearly visible This is the effect of the first reflection floor it affects amplitude evaluation which therefore should have stopped before The time the system evaluate the signal is usually defined as Meter On time This is 112 Chapter 11 Sinusoidal automatically set by CLIO around the value of 6 ms as long as the Frequency involved is high enough to allow this In Fig 11 6 Excel plots the Meter On Time Vs Frequency CLIO uses 100 ral So N N n PSI I E 4 Ooo da EE EH SS ES T E ee ij O i El i fo et Pd LR S ll LI spl l eiii T J TT Oo o ST KE RER re dice WEE Dili ms DU LIL LL Lo ll xvi VI IPN PT Ty DS E I E SS I SRS e NEN E bg Lea I I I DD OO II DL pla IC WEG S ES Si RG Ri eee EE ee EES E ei i ih i E ANE SN NO EC ER SD SI ee TAZZA EE ooo or tp MITI LT TT uni 10 20 50 100 200 500 Hz 10k
2. Figure 10 8 and 10 9 The first relevant difference is the frequency range In the 6 4kHz sampling rate both sides of the resonance are completely visible Thiele and Small parameters derived with these settings are more accurate This is especially true if using the added mass technique Fs is further lowered But more important the impedance at Fs is 115 ohm at 51 2kHz and 1180hm at 6 4kHz 10 4 3 ACOUSTIC FREQUENCY RESPONSE Up to now we measured using CLIO and simple cables Now we are going to deal with acoustic measurement The time domain will be an essential part of our interest Furthermore we need to add two external devices a microphone and a power amplifier Connections are shown in Fig 10 10 INPUT A OR B CLIO OUTPUT A OR B MIC 01 OR MIC 02 Ss BLACK RED RED BLACK POWER AIVPLIFIER Figure 10 10 Please note that the connections from the amplifier to the speaker are inverting polarity This is on the assumption that the amplifier is non inverting most are so and you are using Audiomatica Mic 01 or Mic 02 which does invert polarity Most Measuring Grade Microphone invert polarity Remember that inverting polarity do not change the frequency response It does change phase response Fig 10 11 shows how we placed the microphone respect to the speaker and both respect to the floor 92 Chapter 10 MLS
3. D 10 0 0 00 2000 4000 6000 8000 10000 12000 14000 16000 Hz 18000 20000 0 00 1 00 2 0 3 0 4 0 5 0 6 0 7 0 80 ms 90 10 0 Figure 11 10 Fig 11 11 shows the spectrum when the delay has been set to 1 5ms The third harmonic 64dB 0 06 below the fundamental is clearly visible 10 0 Pa al RR ul 50 D a0 Lag 10 0 0 00 2000 4000 6000 8000 10000 12000 14000 16000 Hz 18000 20000 0 00 1 00 2 0 3 0 4 0 5 0 6 0 7 0 80 ms 9 0 10 0 Figure 11 11 Chapter 11 Sinusoidal 115 Finally Fig 11 12 shows the distortion analysis carried out with the same microphone distance as in the past examples and the gating delay set to 1 5ms with the auto delay option disabled Fundamental is red second harmonic 30dB blue and third harmonic 30dB green 120 0 180 0 dBSPL 110 0 100 0 108 0 180 0 10 100 1k Hz 10k 20k Figure 11 12 116 Chapter 11 Sinusoidal 12 WATERFALL 12 1 INTRODUCTION The Waterfall post processing routines give CLI Owin the possibility of making 3 D plots adding a t
4. 0 2 03mS 7 26mS 10mS SPEAKER MIC Po 70 cm 2 03mS FIRST REFLECTION i i 250 CM 7 26mS 120cm 3 ABSORBING MATERIAL i FLOOR Figure 10 11 Any other reflecting surface is farther than the floor If the microphone is directly connected to the CLIO board remember to switch the microphone power supply on Also very important remember to type in the correct microphone sensitivity in the microphone Dialog Box The last item is crucial for setting the correct measurement level We already dealt we level before Here things are more dangerous Supposing the amplifier used has a gain of 30dB a common value leaving CLIO output level to OdB will cause the amplifier to deliver the equivalent of circa 40W 8Ohm continuous If the amplifier handles this power you will for sure burn your tweeter If the amplifier is of lower power it will saturate and burn your tweeter even faster To avoid this embarrassing event do as follow enable CLIO input auto range open the Multi Meter and select Pressure from the Parameter Drop Down You will get the reading of your environmental noise Fig 10 12 shows ours we hope yours is lower EJ Multi Meter OF x EN Multi Meter Il x TS E its a Hx BQ fPesue zapen lz e Eo zl ss Presse zlla spt SE ep Je Sl ei S ty B Q JPresswe g s zz SE cen zl ss Fressue zllapspt zlS Rp cn zl a e JN MLS WHITE PINK FILE OSN en MLS w
5. 108 0 6624 0 90 0 36 0 9936 0 80 0 36 0 70 0 13248 70 0 7 iT UNITI 108 0 l 60 0 20 2 z 4 46560 60 0 100 1k Hz 10k Ok 20 Figure 10 22 and 10 23 Reader might wonder if these figures are correct at all and if they have same usefulness at least visually Well the curves are absolutely correct their visual usefulness is zero for the wrapped curve and low for the unwrapped Difficulties in getting simple visual information from these curves arise because they are the sum two effects The first one is the device own phase response The second Is the time of sound flight The latter does affect the curves much more than the first one completely burying it The good news is that it is often possible to separate these two effects However bad news this is not an easy task Trying to explain it without going in heavy math is very difficult The bibliography in this user manual should be considered as integral part of it here Within CLIO the time of flight can be removed in several different way with different
6. 2 3 2 USE OF THE PREAMPLIFIER The MIC 01 or MIC 02 microphone cable has to be connected to the preamplifier input while the preamplifier output has to be connected to the analyzer input The unit is Switched on with the POWER switch while the TEST push button controls the state of the unit when pressing it ifthe led light is on then the unit operates correctly otherwise not either the batteries are low or the external power supply is not connected The FILTER switch inserts the weigthing filter To choose the desired weighting filter type and to set the amplifier gain you have to modify the internal settings as described later NOTE tf the 20 dB gain stage Is inserted the overall sensitivity microphone pre is 10 times higher For example if your microphone has a sensitivity of 17 1 mV Pa and you preamplify it of 20 dB then you get a sensitivity of 171 mV Pa Chapter 2 The CLIO System 17 2 4 THE QCBOX MODEL 4 AMPLI FI ER amp SWITCH BOX The QCBOX Model 4 amplifier and switch box is of invaluable help when configuring an automatic or manual quality control setup and even in everyday laboratory use Its main feature is the possibility of internal switching that permits the measurement of the IMpedance and frequency response of the loudspeaker connected to its output sockets without changing the loudpeaker wiring it is also possible to choose one among four inputs for the response measurements the internal switching is under soft
7. Si CLIO ELECTRICAL amp ACOUS File Analysis Controls Window H GG LU Ls Ch S Waterfall Ctrl liu EFT Ctrl F Aa Sinusoidal Ctrl 5 oy Multi Meter F4 Te T amp S Parameters Ctrl T Ur Quality Control Cf Fig 5 11 Analysis Menu CTRL M Enters the MLS Analysis control panel CTRL W Enters the Waterfall control panel CTRL F Enters the FFT Analysis control panel CTRL S Enters the Sinusoidal Analysis control panel F4 Enters the Multimeter control panel CTRL T Enters the Thiele amp Small Parameters control panel CTRL Q Enters the Quality Control Processor ae CLIO ELECTRICAL amp ACOUSTICAL TESTS Fil is Controls Wind Hel EI CLIO ELECTRICAL amp ACOUSTICAL TESTS a ES ee File Analysis Controls Window Help Lex Mus gt Go G Ws 60S Go G S Waterfall Cirle Autosave S waterfall Ctrl Autosave lu EFT uri SE IS FFT CAE Ta fu Sinusoidal Ctrl 5 Process mo Siae SI E i Multi Meter F4 Proce ig Tools Ss Multi Meter F4 Processing Tools o de age a SE a To T amp S Parameters Ctrl T Settings 5 Lean SUA ER Time T Hu Quality Control Ctrl G pe T Frequency F ES Frequency F Impulse Step Phase Group Delay Schroeder Decay ETC ont fea et Fig 5 12 MLS Submenu G Starts an MLS measurement Equivalent to n S Enters the Settings dialog box Equivalent to dh T Enters the MLS Time domain Equivalent to L 48 Chapter 5 CLI Owin basics F Enters the MLS Frequency
8. To continue click Next lt Back Cancel Figure 3 12 At the successive prompt Select Specify a location then insert the CLI Owin CD ROM in the CD ROM drive and press the Browse button Choose the CLIO2K I NF file inside the INF2K directory inside the CD ROM see Fig 3 13 Found New Hardware Wizard Found New Hardware Wizard Locate Driver Files Dags Driver Files Search Results Dags Where do you want Windows to search for driver files SY The wizard has finished searching for driver files for your hardware device SY Search for driver files for the following hardware device The wizard found a driver for the following device ay Multimedia Audio Controller oy Multimedia Audio Controller The wizard searches for suitable drivers in its driver database on your computer and in any of the following optional search locations that you specify To start the search click Next If you are searching on a floppy disk or CD ROM drive insert the floppy disk or CD before clicking Next Windows found a driver for this device To install the driver Windows found click Next d inf2k clio2k inf Optional search locations IT Floppy disk drives I CD ROM drives quesesseezeseazesezaseezeo sese esa sezenenta IT Microsoft Windows Update lt Back Cancel I Cancel Figure 3 13 24 Chapter 3 Installation Ignore Microsoft s warning message about Digital Signature answer Yes to the
9. ELECTRICAL amp ACOUSTI CAL TESTS CLIOwin 6 5 Italy Audiomatica Florence GL sh 4 E e E geg u 3 n e ke 3 gt E a E 2004 p t 1991 S reserved All gh t to All r Cop User s Manual Version PCI AUDIOMATICA Copyright 1991 2004 by AUDIOMATI CA SRL All Rights Reserved Edition 6 51 PCI March 2004 IBM is a registered trademark of International Business Machines Corporation Windows is a registered trademark of Microsoft Corporation CONTENTS TINTRODUCG FION cin 9 Ms Mise EN THO MANUAL speren E aa 9 1 1 1 WHAT THIS USER MANUAL DOES COVER eine 9 1 2 GENERAL CONDITIONS AND WARRANTY 9 2 TAE GLO SYSTEN iaia dirsi cana rie 13 2 1 THE PB 4281 PC BOARD AND SC 01 SIGNAL CONDITIONER eee eeeeeeeeeeeeeeeeees 14 2 1 1 GONMBINEDTECANICALSPECIFIGATONS genialata 14 RR eeh We LEE leali 15 22 1 THE MIC Te ele ET 15 2 2 2 ECANICALSPEGIFICANONS priori 15 2 2 3 THE MIC 01 OR MIC 02 FREQUENCY CALIBRATION DATA 16 2 24 THE MIC 01 OR MIC 02 LITE MICROPHONE ege agehusgeeg eeben ege deb eege 16 2 3 THE PRE 01 MICROPHONE PREAMPLIFIER Gli 17 2 3 1 TECHNICAL SPECIFICATION Graie ri 17 232 USE OF THE PREAMP EIF IE Fi Licio 17 2 4 THE QCBOX MODEL 4 AMPLIFIER amp SWITCH BOX nasssnssssssssnsnsessnnnnrensssnnrrrenrrnnrrreerrnnnneee 18 2 4 1 TECHNICAL SPECIFICATIONS riali AE 18 3 CLIO INSTAELATON H 19 3 1 MINIMUM PC CONFIGURATION E 19 32 HAR
10. Soc 1972 June Bibliography 143 19 M O Hawksford Digital Signal Processing Tools for Loudspeaker Evaluation and Discrete Time Crossover Design J Audio Eng Soc 1997 January February 20 D Clarke Precision Measurement of Loudspeaker Parameters J Audio Eng Soc 1997 March 21 IASCA International Auto Sound Challenge Association Inc Official Judging Rules 144 Bibliography
11. invoked from there it is possible to choose the output signal to be generated The default signal at startup is a 1kHz sinusoid AN Start playing Cancel Figure 5 3 generator drop down menu Note this drop down menu will appear also clicking the SET button within the Multi meter control panel 8 3 1 It is possible from here to define three kinds of signals or choose from a signal file list Once you have defined the signal you want to play then you will control generation simply with the toolbar button di The signal will remain defined until next user definition The default signal is a 1kHz continuous sinusoid Check PromptOnPlay if you want to be prompted Fig5 3 before the generator Starts playing di OdBY a Sin TwoSin Mls File PromptOnPlay Figure 5 4 Generator drop down menu Chapter 5 CLIOwin basics 41 It Is possible to generate the following signals Bursted sinusoid you can input the sinusoid frequency if you leave Time On and Time Off at zero the signal is continuous Generator Input Form Two tones signal you can input each tone frequency and relative level Generator Input Form 1000 00 2000 00 oo oo an MLS sequence you may choose among different sequence lengths Generator Input Form Generator Input Form Select a Signal File 21x face A fea J ALL32768 MULTI1024 iq LLaog6 Ki MULTI2048 Kd ALL512 Ki MULTIA096 iid LLe192 Ki MULTIS12 I KBJI
12. see FFT mouse left down activates the marker mouse left drag moves the marker mouse wheel up equivalent to A mouse wheel down equivalent to w Chapter 7 Common Measuring I nterface 67 7 6 THE MLS TI ME DOMAIN DISPLAY When entering the MLS time domain you will find a slightly different display Fig 7 2 a Sx QQ 44 4 4 a E EEA EE E d GE cea wll e wn el n EE E KE vs bss kbessbe zb zk zs E A E E DEE ed EE ee ee EON DEEE DEE Se be aE oe EEN GER bee Sk ok ee l I Li I I L I I L I I L I I L I I r r r r 3 A Sees ee baue 0 00 8 0 16 24 ES 40 de 56 64 me Ye 80 Figure 7 2 In this case there are no overlays It is also possible to select a portion of the active curve by means of three particular buttons The selected portion of the active curve Is identified by a start and stop point and is draw in a different color from the unselected portion ie Defines the start point of the selection 4 Defines the stop point of the selection Returns the curve to a completely unselected state 68 Chapter 7 Common Measuring I nterface 8 MULTI METER 8 1 INTRODUCTION The Multi meter is an interactive real time measuring instrument It gives CLIOwin the functionality of a Sound level meter dBSPL dBA dBC Millivoltmeter V dBV dBu dBr Frequency counter Hz Distortion meter dB L C R bridge H uF Ohm Recallable simply pressin
13. 0 1dB Shitt F7 8 Ch A In Gut Loop 5 ChE In Gut Loop a Input Auborange Input Full Scale 10dB FIO Input Full Scale 10dB FA Ty Mic Power Supply Ctrl P gf Mic Settings Shift F1 External Hardware Shift F4 Fig 5 18 Controls Menu ESC Immediately kills the generator Equivalent to releasing di SHIFT F8 Increases the output level of 0 1dB Equivalent to SHIFT A F8Increases the output level of 1dB Equivalent to a F7Decreases the output level of 1dB Equivalent to SHIFT F7 Decreases the output level of 0 1dB Equivalent to SHIFT F10 Increases the input acceptance of 10dB Equivalent to a F9 Decreases the input acceptance of 10dB Equivalent to wr Chapter 5 CLI Owin basics 51 CTRL P Swithces on and off the microphone power supply Equivalent to Ty SHI FT Fl1 Enters the Mic settings dialog Equivalent to gf SHIFT F4 Enters the External Hardware control panel Equivalent to 5 6 4 WINDOWS MENU The Windows Menu helps you manage all opened windows i e measurement control panels in a standardized way You can Tile or Cascade the open windows or access each one directly ga CLIO ELECTRICAL amp ACOUSTICAL TESTS Fig 5 19 Windows Menu 5 6 5 HELP MENU From the Help Menu you can access all the available help resources installed in your computer or available directly from Audiomatica over the internet ma CLIO ELECTRICAL amp ACOUSTICAL TESTS Fig 5 20 Help Menu FlIin
14. 10 34 102 Chapter 10 MLS We set the impedance to 8 ohm as this is the nominal impedance of the tweeter Clicking Ok we obtain Fig 10 35 which is the final result 108 0 180 0 20 100 1k Hz 10k 20k Figure 10 35 Our last example will cover the merge function When we measured the system of Fig 10 17 we stated that the lower frequency limit that had to be considered reliable was 208Hz We can easily overcome this limit taking another measurement with the near field technique and merge the result with the data of Fig 10 17 Doing near field measurement you should readjust the output level so that the maximum sound pressure does not exceed 110dBSPL as this prevent Microphone overload problems Fig 10 36 shows both the near field and far field response Notice the big level difference To merge them the far field should be the one in memory Fig 10 37 shows the Merge Dialog with a transition frequency set to 350Hz 180 0 GR Aa Nk See RAGA Du File Trans Freq Hz p50 ben FileName rogemear mis Browse 108 0 Ok Cancel d 180 0 20 100 1k Hz 10k 20k Figure 10 36 and 10 37 Fig 10 38 shows the merged response Notice that the near field measurement level has been scaled to the far field one Two very important func
15. 3 or 1 6 octave bands turning the instrument into what is generally called a real time analyzer RTA The ability to process two channels simultaneously to select the appropriate sampling frequency and the possibility of triggering with respect to the generated signal make this control panel a flexible and valuable instrument Finally there is also a very useful facility to quickly and easily swap back and forth between the time and frequency domains 9 2 FFT CONTROL PANEL HA FFT 143 OCTAVE Tell IL Gs i Rectangular sl JEJ sl 20 I qa DOAMEOAC earn dh GK LOHR Ii LITTA TS LIL Prati SEL 2U 100 Ok 2Uk Filename CHA dBY 5l 2kHz 16384 Rectangular Fig 9 1 The FFT control panel Fig 9 1 shows the FFT and RTA control panel Follow a description of the FFT control panel toolbar and settings RTA operation is obtained simply by selecting the appropriate frequency axis property either 1 3 or 1 6 of octave within the FFT settings dialog see 9 3 When operating as RTA the FFT window s title is changed as in Fig 9 1 in FFT 1 3 OCTAVE or FFT 1 6 OCTAVE For a detailed description of the graphical display common also to other measurement control panels and its capabilities please refer to Chapter 7 For a description of the available shortcuts please refer to section 5 5 2 Chapter 9 FFT 77 9 2 1 TOOLBAR BUTTONS ty Starts an FFT or RTA measurement Pressing the drop down menu it is
16. 8 Multi Meter 71 This operating mode is very useful as an example suppose you want to measure the total harmonic distortion of a sinusoidal signal while displaying also its frequency content To do this lets invoke the FFT and Multi meter control panels together then press the Go button in FFT this will start both measurements see also 8 6 about this inside the Multi meter select the THD parameter and then press the minimized button You should obtain a measurement situation like the one in Fig 8 3 In this figure we were acquiring directly the output of CLIO while generating a 1kHz sinusoid at OdBu Ma FFT 210 x E e rnr L rn o Hanning jfa sl fn 1 i 0 00 2000 4000 6000 8000 10000 12000 14000 16000 Hz 18000 20000 Filename CHA dBY 51 2kHz 4096 Hanning Z Figure 8 3 8 3 3 CAPTURI NG THE GLOBAL REFERENCE LEVEL Let s see now how to capture a level to be the reference for other measurements Once this is done then the subsequent measures done in all the instrument with the units dBRel selected will refer to it As an example we go back to the procedure described in 3 5 1 which aims at validating a calibration This is substantially the measurement of the frequency response of the CLIO board itself which is when calibrated a straight line as said in the cited procedure the acquired level of such a measurement is 5 2 dBV Let s see a practical way to acquire this level in order to refer future measuremen
17. AND DEMO MODE Each CLIO system has its own serial number which plays an important role since the CLIOwin software is hardware protected and relies on a correct serialization in order to run Refer to 3 5 to identify your system s serial number If the CLIOwin software doesn t find a CLIO Box with a correct serial number gives a warning message and enters what is called DEMO mode in this way it is possible to run CLIOwin in a PC where the CLI O hardware is not installed while still allowing you to perform post processing and other off line jobs Chapter 3 Installation 35 36 Chapter 3 Installation 4 TROUBLESHOOTI NG CLI O INSTALLATI ON To receive assistante please contact Audiomatica at info audiomatica com or connect to our website www audiomatica com Chapter 4 Troubleshooting CLI O I nstallation 37 38 Chapter 4 Troubleshooting CLI O I nstallation 5 CLIOWI N BASI CS 5 1 INTRODUCTION This chapter gives you the basic information about CLIOwin and the related hardware and how to connect and operate it then you should refer to the various measurement specific chapters to go into more details of single measurements Chapter 6 deals with other general functionality of CLI Owin Here you will find information about Help Main desktop toolbar and menu Shortcuts Generator Input and Output Microphone Amplifier amp SwitchBox Turntable Connections 5 2 GETTI NG HELP BA CLIO ELECTRICAL amp ACOU
18. Let s now check what driver XP installed Click with the right mouse button on the My Computer icon on the Windows desktop Then click Properties select the Hardware tab and press the Device Manager button as in Fig 3 17 Device Manager File Action View Help 4 3 Ra E PROGRAMMAZIONE Ta Di A Computer H Disk drives o S Display adapters A DYDICD ROM drives LN Floppy disk controllers i Floppy disk drives AE IDE ATASATAPI controllers KZ Keyboards Open E Mice and other pointing devices Explore a e Monitors Search HE Network adapters H Ports COM amp LPT i MP Processors Map Network Drive 2 Sound video and game controllers E Audio Codecs Ei CMI8738 C3Dx PCI Audio Device Create Shortcut i l sd y Crystal SoundFusion tm C54281 Joystick Delete i if Crystal SoundFusionitm C54281 WDM Audio Rename ved 2 Legacy Audio Drivers jo pe y Legacy Video Capture Devices AQ Media Control Devices Standard Game Port jo il EI video Codecs 2 System devices A My Compo ee Manage Disconnect Network Drive H Universal Serial Bus controllers Wel Figure 3 17 XP Installed a driver for the Crystal hardware accelerator that the CLIO PB4281 card is using Press the Update Driver button and enter the Hardware Update Wizard Fig 3 18 Select Install from a list or specific location Advanced and click Next then
19. SZ aa WDOBOBOAAL ay 20 0 180 0 10 0 Z 108 0 AA E IL a ot ELUTE EI a ee fa TUTTII TO TT 0 100 1k Hz 10k 20k 20 0 30 0 Filename CHA dBRel Unsmoothed 51 2kHz 16K Rectangular 4 Figure 8 5 8 4 THE SOUND LEVEL METER Selecting Pressure as measured parameter gives your Multi meter the functionality of a Sound Level Meter Three units are available ABSPL dBA and dBC dBSPL is a direct reading of the sound level relative to the reference pressure of 20uPa Remember that CLIOwin needs to know your microphone sensitivity to correctly execute this measure ment see 5 4 4 dBA and dBC are frequency weighted measurements and are usually requested to assess for example environmental noise or any human related annoy ance In these two cases the program postprocess the measurement applying the appropriate frequency filter as described in EC 651 norms 8 4 1 CAPTURING THE MICROPHONE SENSITIVITY When measuring pressure it is possible to calibrate your measuring chain if you have available a pressure reference like an acoustic calibrator It is possible to calibrate both channels In this situation in fact the button if pressed will prompt the instrument to capture a pressure reading as reference for the reading channel it also expects that the reference pressure level at its input is 94dB as furnished by the vast majority of acoustic calibrators As result of this procedure the program will calculate the sensi
20. Shift ms 0 00 Mme Stitt ins o 00 j Za Fia Z Ref window Rise Time ms 0 58 window Aise Time ms 0 58 Starr eaueneri Hg Start Frequency Hz Reference n Reference IT Lied Stop Frequency Hel Stop Frequency Hz 7 Save Settings Save Settings Default Cancel Figure 12 2 Within the waterfall settings dialog Fig 12 2 it is possible to configure many waterfall parameters But since the calculation relies on externally available data it also captures some settings from the data source itself When executing CSD and ETF waterfalls the data source is the MLS control panel when displaying files the data source is obviously the set of files Itis possible to save and load from disk executed waterfalls One automatic setting is Y scaling The waterfall amplitude scale is always dB relative the routine try to evaluate the maximum value within all the data to be represented and references all other values to this The first setting encountered is Mode that selects between the available modes CSD ETF and File Follow a basic introduction to the three different modes 12 3 1 CSD AND ETF MODES SETTINGS AND OPERATION Number of Spectra Selects the number of data slices to display Time Shift ms Selects the time between two consecutive spectra Window Rise Time ms Selects the rise time of the data selecting window Valid only for CSD Reference If checked the waterfall spectra will
21. Speed RPM 0 750 Resolution Deg 5 0 Figure 12 11 12 5 3 TAKING THE MEASUREMENTS You are now ready to begin the measuring session We suggest you to take one first measurement with the speaker in place over the turntable to verify all the parameters especially viewing the acquired impulse response and setting the start and stop values of the measurement window These values will be applied to all the measurements taken consider in this respect the problem of the trajectory of the acoustic center of the speaker during the rotation The last thing to do is to activate Autosave and Loop to do this we press the corresponding toolbar buttons Fig 12 12 BA MLS Frequenc S Blo si Figure 12 12 Press Go After each MLS measurement is taken you will see the turntable rotating and CLI Owin waiting for a time sufficient for the turntable to stabilize before automatically take the next measurement Should this time not be sufficient you have to reset the turntable speed value accordingly The autosave function will refresh the filename after each measure Fig 12 13 Filename rcf deg 4500 mls Figure 12 13 After the 25 measurements are taken the session should end while the autosave and loop buttons reset 12 5 4 REPRESENTING POLAR DATA WITH A WATERFALL To represent the measured data we need to enter the Waterfall Settings dialog select the File Display mode and then press the browse butto
22. To perform a measurement it programs the FFT routines changing FFT settings to match its needs and then effectively starts an FFT measurement in background The two panels can be opened and can work together but FFT always acts as master while Multi meter as slave In this situation the Multi meter window s title is changed to Multi Meter FFT slave to reflect this new state the Go and Stop buttons are disabled as you operate the slave panel from inside FFT starting and stopping the reading with the FFT s Go and Stop buttons the input channel follows the FFT one while the integration setting become meaningless this is because the user s has control over FFT averages which precisely define the measurement integration Nevertheless during slave operation it is possible to select the displayed parameter and its unit It is not possible to select LCR operation as LCR meter uses different measurement capabilities As soon as the FFT control panel is closed it releases Multi meter from the slave state then Multi meter is ready from stand alone operation and Is fully functional as described above Chapter 8 Multi Meter 75 76 Chapter 8 Multi Meter 9 FFT AND RTA 9 1 INTRODUCTION By selecting the FFT command from the main menu bar it is possible to carry out Fourier analysis of the input signal to determine its frequency content using the Fast Fourier Transform FFT The processed data can be displayed as narrowbands or 1
23. amp S gt T amp S Parameters 6 3 4 EXPORTING GRAPHICS File gt Export gt Graphics CLI Owin is able to create enhanced metafiles emf or bitmaps bmp of the currently active measurement The graph is drawn using the same color of printouts you can define them with the Setup dialog see 6 3 6 Export Graphic File T Black vhite Cancel Fig 6 6 Export Graphics dialog When exporting bitmaps check the Black amp White box to greatly reduce the size of the generated file while loosing color information Chapter 6 System Operations and Settings 61 6 3 5 CALIBRATION File gt Calibration This option will perform a calibration of your CLIO hardware Please refer to paragraph 3 7 and follow the procedure described In order to determine at any given time if it is necessary to calibrate CLIO do the following Let the system warm up Proceed to perform the verification described in 3 7 1 Consequently decide whether or not to calibrate The result of the measurement may vary in some way from the time we calibrated because of many small changes in measurement conditions including changes in the atmospheric conditions the season and the mains voltage Note the CLI O hardware is highly precise and stable and under normal operating conditions does not require frequent calibrations Always perform a calibration if You reinstalled CLIO in a different computer You installed a software upgrade 6 3 6
24. autosaved file will be named c clio2000 data rcf deg 4000 Total Number defines the number of autosaved files after which the process is automatically ended It is possible to choose to save in the standard binary file format Bin and or to export in text format Txt see also 6 3 3 the drop down chooses number of export data points for MLS files It is possible to save and load these definitions in particular files called Autosave Definition Files asd Chapter 6 System Operations and Settings 59 Enters the Notes dialog where it is possible to input comments to be saved with the actual measurement and inspect other measurement information Check boxes enable for printing notes and exporting notes to graphics files Notes about measurement check boxes to print X M Measure MLS Frequency Response k Date 07 03 02 Time 15 36 44 lt 1 File Name lt I Company Audiomatica Srl Di Settings CHA dBY Unsmoothed 48kHz 16K Rectangular Start 0 00ms Stop 341 31ms FregLO 2 93Hz MW Notes E Cancel Fig 6 4 Notes dialog 6 3 2 PRI NTI NG Prints the current active measurement The definition of printing colors is done with the Setup dialog see 6 3 5 6 3 3 EXPORTING DATA File gt Export gt Data CLI Owin is able to export the currently active measurement in an ASCII file txt Export S Frequency Data di Cancel Fig 6 5 Export dialog Performing this choice y
25. be reference to the rearmost one As already said the data source for a CSD or ETF waterfall is the MLS control panel when in these modes the Go button becomes active only if there is an MLS measurement active i e just executed or loaded from disk The waterfall captures the following MLS settings frequency range if MLS has a zoomed curve than waterfall will take the selected zoom as frequency range to display smoothing the current MLS smoothing factor is also applied to the calculated data slices start time the Start Window value selected in the MLS impulse response represents time zero for the waterfall stop time the Stop Window value selected in the MLS impulse response represents the last processed CSD slice unless a different Time Shift has been selected You can interactively switch between the MLS and Waterfall control panels to change the MLS settings that affect waterfall CSD Cumulative Spectral Decay is intended primarily for anechoic loudspeaker 118 Chapter 12 Waterfall evaluation in this case only the data between the start and stop time is analyzed each successive slice considers time data from its relative start time the rearmost at time zero has start time equal to the start window of MLS to the fixed stop time the data being windowed by a particular time window with a smoothed rising edge see literature for a discussion about this Normal values for the Window Rise Time lie within 0 1 and 0 6ms In CSD mo
26. button ter Then click onthe MLS II button to invoke the MLS control panel Press the Go E button to execute an MLS frequency response measurement after about 1 second you should obtain the desired result a straight line blue as in Fig 3 29 You can click on the graph and inspect the amplitude of the measured signal you should obtain a reading around 5 2dBV this is the correct output level of the MLS signal with the generator output set to OdBu Now click on the Sinusoidal button o to invoke the Sinusoidal control panel as in Fig 3 29 Press the Go mt button to execute a Sinusoidal frequency response measurement after about 3 seconds you should obtain the desired result again a straight line blue as in Fig 3 29 You can click on the graph and inspect the amplitude of the measured signal you should obtain a reading around 2 2dBV this is the correct output level of the sinusoidal signal with the generator output set to OdBu To ensure a 100 correct calibration you also need to inspect the phase responses of both measurements To do this press the phase button and verify that you obtain a straight line red curves in Fig 3 29 the readings in this case should be around zero degrees in both cases As afinal test repeat the 1kHz tone test described in 3 5 1 The expected result is shown in Fig 3 30 34 Chapter 3 Installation ae CLIO ELECTRICAL amp ACOUSTICAL TESTS Figure 3 30 3 8 CLIO SERIAL NUMBER
27. compatible file to the current measurement AS Multiplies the current measurement by a data value or compatible file Divides the current measurement by a data value or compatible file Hi Shifts the current measurement by a dB value x t Multiplies the current measurement by complex frequency Divides the current measurement by complex frequency FP Uses a reference measurement file taken at speaker terminals to calculate 1m sensitivity in dBSPL W The reference file should have dBV Y units while the one in memory should be in dBSPL E3Temporally shifts the current measurement by a ms value Affects phase response Merges the current measurement with the part below the selected transition frequency of a selected compatible file CI Combines the current measurement and the selected file to obtain a constant current impedance measurement Both files should be in dBV ei Combines the current measurement and the selected file to obtain a constant voltage impedance measurement Both files should be in dBV Chapter 11 Sinusoidal 109 11 3 A BRIEF DESCRIPTION ON SETTINGS EFFECTS 11 3 1 STEPPED VS NOT STEPPED Although Measuring speed increases use of a not stepped sweep can adversely affect measuring results in several circumstances As an example that should make clear also other situation let s see what happens measuring the impedance of a woofer in Internal or Constant Current Mode Please refer to Measuring Impedance for
28. degree of accuracy The most accurate is also the most complicated and is how we are going to proceed Fig 10 24 introduces us to Mintmum Phase which is the hearth of the whole procedure 110 180 0 oo CLIO dBSPL Deg 100 0 FH 108 0 108 0 60 0 180 0 20 100 1k Hz 10k 20k Figure 10 24 We obtained it selecting minimum phase in the MLS Setting and calculating the phase again Certain well behaved systems are defined as Minimum Phase In these the phase response can be obtained from the magnitude response by calculation Another kind of phase we promise is the last one is Excess Phase This is the algebraic difference between true phase as in Fig 10 22 and minimum phase It is exactly what we need to separate the time of flight from the device own phase response We wont use excess phase directly here but a post process of it Excess Group Delay Fig 10 25 Is the excess group delay of our tweeter vs frequency Chapter 10 MLS 97 It was obtained selecting Excess in the Setting Dialog and clicking on the Group Delay button This graph represents the distance of the sound source from the microphone vs frequency As long as the distance is constant the system is minimum phase and we are in presence of a well defined acoustic centre Recall from previous paragraphs that we have reliable data down to 200Hz because of the time windows As
29. has the same select the CV icon and input the data you should know 180 0 k The Ohm value is that of the Sensing Resistor while in the edit box you see the name of our previous file cvreference sin added by its own path which could be different in your case Hath Dialog TFEX te MO AGC File R onm fi FileName Jevreference sin Browse Cancel 134 Chapter 13 Measuring impedance and T amp S parameters Pressing Ok we get Fig 13 15 which is our final result Note that the Y Units have been changed to Ohm This result is only in memory and should be saved now for further use 10 100 1k Hz 10k 20k Figure 13 15 13 5 2 CONSTANT CURRENT We will go quicker now as its very similar to what we have just seen Connections for creating the reference are the same please refer to Fig 13 11 Again everything should be left unchanged between creating the reference and the device files The big difference from before is the output level We choose here a 1Kohm resistor This will attenuate a lot the signal at loudspeaker terminal Fig 13 16 shows the reference measurement 180 30 0 CLIO 80 0 20 0 108 0 10 0 108 0 20 0 180 0 10 100 1k Hz 10k 20k Figure 13 16 We have a straight line again notice the le
30. input channels can be controlled separately or as a single balanced one A switchable phantom supply lets you directly connect an Audiomatica MI C 01 or MIC 02 microphone to any of the SC 01 Inputs It is also possible to superimpose a DC voltage to the genarated AC signal 2 1 1 COMBINED TECHNICAL SPECIFICATIONS GENERATOR Two channels 18 Bit sigma delta D A Converter Frequency range LHz 22KHz Frequency accuracy gt 0 01 Frequency resolution 0 01 Hz Output impedance 150 Ohm Max output level Sine 12dBu 3 1 V RMS Output DC Ch A 2 5V Attenuation 0 1 dB steps to full mute THD Noise Sine 0 01 ANALYZER Two channels 18 bit sigma delta A D Converter Input range 40 40dBV Max input acceptance 40dBV 283Vpp Input impedance 64 KOhm 5 6 KOhm mic Phantom power supply 8 2V PC SYSTEM RESOURCES One free IRQ One free RS 232 port MISCELLANEOUS Sampling frequency 48KHZ 8KHz Card type 12cm PCI slot card Audio connections four RCA plugs 14 Chapter 2 The CLIO System 2 2 THE MI C 01 MI CROPHONE The MIC 01 microphone is an electret measuring microphone that is particularly well Suited to be used in conjunction with the other components of the CLIO system It IS furnished with its own stand adaptor and a calibration chart reporting the individually measured sensitivity all fittedin an elegant case Its long and thin shape renders it ideal for anechoic measurements Because its frequency respons
31. possible to select the Continue switch In this mode the measurements is not started from blank but accumulates with the previously stopped one see Averaging 9 6 for details Stops the current measurement LU Selects Internal Trigger operation When pressed the acquisition is triggered by the generated signal at Activates the Time Data display Enables the Hold function Depending on the setting entered in the FFT Settings dialog box it is possible to hold either the minimum or maximum value per frequency point Enters the FFT Settings dialog box 9 2 2 TOOLBAR DROP DOWN LISTS AND DISPLAY data window Selects a weighting data window among the following Rectangular no window Hanning Hamming Blackman Bartlett triangular FlatTop channel display Selects the input channel or function to display Y scale units Selects the measurement units target averages Inputs the total number of averages Averaging is controlled by the setting in the FFT Settings dialog see Averaging 9 6 for details number of averages display Displays the number of the actual average this number increases during the measurement unless while in exponential averaging the target has already been reached see Averaging 9 6 for details 78 Chapter 9 FFT 9 3 FFT SETTINGS DI ALOG FFT Settings Fig 9 2 The FFT settings dialog box FFT Size Selects the number of samples acquired and processed by each FFT It is p
32. select Don t search will choose the driver to install and click Next again 26 Chapter 3 Installation Hardware Update Wizard Hardware Update Wizard Welcome to the Hardware Update Please choose your search and installation options Dags SS Wizard This wizard helps you install software for Search for the best driver in these locations Crystal SoundFusion tm CS4281 WDM Audio Use the check boxes below to limit or expand the default search which includes local paths and removable media The best driver found will be installed Vas Search removable media floppy CD ROM If your hardware came with an installation CD A ECH or floppy disk insert it now Include this location in the search L AInf2 What do you want the wizard to do 3 i R Don t search will choose the driver to install O Install the software automatically Recommended Choose this option to select the device driver from a list Windows does not guarantee that Install from a list or specific location Advanced the driver you choose will be the best match for your hardware Click Next to continue Figure 3 18 Insert the CLI Owin CD ROM press Have Disk and choose the CLIO2K INF file inside the INF2K directory of the CD ROM see Fig 3 19 Locate File Look in 2 Inf2k Ode DB clozk inf Install From Disk Insert the manufacturer s installation disk and then es make sure that the correct drive i
33. so it is necessary to input the sensitivity of the microphone in mV Pa b you are using the PRE 01 preamplifier it is necessary to know its internal gain if itis OdB then input the microphone sensitivity if it is 20dB then input the microphone sensitivity multiplied by 10 NOTE It is necessary to input two separate sensitivities one for channel A and one for channel B When it is selected the A B balanced input configuration see 5 7 1 the software will use the channel A sensitivity Please refer also to 8 4 1 where it is described a procedure for assessing the sensitivity of the microphonic chain using an acoustic calibrator capable of producing 94dBSPL It is also possible to activate the Microphone Correction check boxes if activated the software will correct the measured curve according to the data stored in the MICA CAL and MICB CAL files one for each input channel The example below shows a sample text file created to store the microphone frequency response Freq dB Phase 1000 0 0 4000 0 25 0 8000 0 33 0 10000 0 5 0 15000 dt E 0 20000 2 5 0 NOTE This correction will take effect in the MLS and Sinusoidal measurements only 5 4 6 AUTOSCALE lg Enables autoscale When autoscale is active the software during measurements determines optimum Y scale settings 44 Chapter 5 CLI Owin basics 5 5 EXTERNAL HARDWARE CONTROL Ginter the External Hardware Controls dialog box This dialog box performs contro
34. the Settings Dialog Again once the measure has been taken data are immediately converted Smoothing Allows to select a Frequency smoothing of the active curve The smoothing algorithm averages all the value within the selected fraction of octave band surrounding each analysis Frequency It is a non destructive post process that can be applied or 106 Chapter 11 Sinusoidal removed at any moment after the measurement has been taken 11 2 3 SINUSOI DAL SETTI NGS DI ALOG Sinusoidal Settings Gating Impedance Gated Delay ms 0 000 Sweep 4 Stepped Resolution E Octave Ce Internal QC Bos Sense Distortion Freg Max Hz eee tts Freg Min Hz 10 TT Auto Delay Auto Del Fre 10000 Rise dB 30 000 Default Cancel TT Save Settings It is undoubtedly the most important User Interface of the entire Menu Here the single action of every control is considered Theoretical and practical effects on the subsequent measurement are considered later Sweep Settings Stepped Check Box Lets the user choose between continuous or stepped Logarithmic Sweep Continu ous sweep Is faster but therefore should be used only if its clear to the user how this affects the measure Resolution Drop Down Lets the user choose between five different Frequency resolutions It affects the measurement execution time whatever are the other settings Freq Max Edit Box Lets the user de
35. the following success message Fig 3 9 Add New Hardware Wizard CLIO PB4281 PCI Audio Windows has finished installing the software that your new hardware device requires i Cancel Figure 3 9 Let s now verify that the hardware installation and registration is OK Click with the right mouse button on the My Computer icon on the Windows desktop Then click Properties and select the Device Manager tab as in Fig 3 10 System Properties General Device Manager Hardware Profiles Performance Ze View devices by woe View devices by connection Floppy disk controllers Sy Hard disk controllers ES Keyboard ER Monitors Ey Mouse o S Network adapters Explore a Ports COM amp LPT ei Sound video and game controllers Find Cas CLIO PE4291 PCI Audio RS a d i C Media PCI Audio Legacy Device Mu Diocumen Map Network Drive lf CMIS738 C30x PCI Audio Device da DOS Mode MPU 401 Emulator i 0 Gameport Joystick __rr___eedJdg9 i BI MPU 401 Compatible fy Create Shortcut 2 Sustem devices EL Universal Serial Bus controllers Disconnect Network Drive Rename E gle Properties Refresh Print Plorer topete Close one Figure 3 10 The presence of the CLI O PB4281 PCI Audio under Sound video and game controllers confirms the correct installation Chapter 3 Installation 23 3 3 2 HARDWARE REGISTRATION UNDER WINDOWS 2000 Th
36. time will be referenced to the start window instant the Z axis will range exactly the difference between stop and start window points unless a Time Shift is chosen Bom Bi ell Ha fese E2 0ctave E 0 00 1247639 39 58 77 97 12 14 15 ms 17 19 Filename rof0 mls CHA dBY Unsmoothed 51 2kHz 16K Rectangular Figure 12 3 Going to frequency domain we zoom our Measurement between 200 and 20000Hz and apply 1 12 octave smoothing as in Fig 12 4 As said before these parameters will be valid for the waterfall too We are ready for a waterfall now Ee ER SS I d cHa sllespt Mfi2octave Sl aver aa DD8IDDr ay 110 0 180 0 dBSPL Deg 100 0 108 0 ET TT YET AT Ltt 100 Filename rcf0 mls CHA dBY Unsmoothed 51 2kHz 16K Rectangular 90 80 0 0 108 0 180 0 Figure 12 4 Let s invoke the waterfall control panel The Go button should be enabled Press it you should obtain a waterfall like the one in Fig 12 5 120 Chapter 12 Waterfall Figure 12 5 One powerful way to inspect a waterfall is to enable its marker Press the A button The display should change as in Fig 12 6 Itis very easy to locate frequency zones where the decay suffers like the peak around 2200Hz After placing the cursor on it is quickly possible to move back and forth the calculated slices by means of the up and down keyboard arrows Figure 12 6 Let s now change the CSD as
37. to overcome noise is increase level One way is to put more voltage at the Loudspeaker terminals unfortunately this increase distortion by its own even if it provide important information regarding the device The second way is to narrow the Microphone to Loudspeaker distance The next figures dealing with Gating Effects refer to a 114 Chapter 11 Sinusoidal Microphone 11 5cm 4 5 infrontto a good quality tweeter FFT size is set to 512 points the equivalent of 10ms Meter On at 51200Hz sampling rate Fig 11 9 shows the effects of a wrong delay in capturing a 2kHz 10ms tone burst All harmonics are buried below the effects of this wrong set 0 10 0 0 00 2000 4000 6000 8000 10000 12000 14000 16000 Hz 18000 20000 0 00 1 00 20 30 40 50 6 0 70 80 ms 90 10 0 Figure 11 9 Fig 11 10 shows the effects of the device settling time as the delay is now correctly set to 0 35ms 40dB down harmonics 1 distortion should be visible now As the tweeter perform better than this what we see is the second harmonic cancelling the broad spectrum caused by the device settling time
38. 13 1 In principle Internal mode is very similar to Constant Current Takes advantage on the knowledge CLIO has of its own output level and output impedance 150 Ohm 0 1 In fact this value is lower than what should be used for true Constant Current procedure Veterans should not worry Even if the resistor value is on the same order of magnitude of the device you are going to measure instead of 10 times higher as usually advised no errors occurs as CLIO Is able to acquire and evaluate the signal at device terminals as complex real and imaginary Fig 13 1 shows the connections for measuring Impedance in Internal mode Only one cables pin to alligators like the one in the photo needed without any other external active or passive device Before starting any impedance measurement in Internal Mode remember to switch on the loop button or o of the channel you are going to use Chapter 13 Measuring impedance and T amp S parameters 127 If you are novice in using CLI O or to impedance measurements in general use this mode also do not start measuring loudspeaker impedance immediately Get a 22 to 100 Ohm resistor possibly 1 tolerance and make your experience with something you can expect the results you should get Here are two examples both with Sinusoidal and MLS Before you press go remember to set the Y scale to Ohm We choose a 47 Ohm resistor The modulus should be very close to the resistor value red curve and phase impor
39. 1988 May 7 J Vanderkooy and S P Lipshitz Uses and Abuses of the Energy Time Curve J Audio Eng Soc Vol 38 1990 November 8 G Ballou Handbook for Sound Engineers The New Audio Cyclopedia Howard W Sams amp Company 1987 9 D Davis ang Davis Sound System Engineering Howard W Sams amp Company 1987 10 R H Small Simplified Loudspeaker Measurements at Low Frequencies J Audio Eng Soc 1972 Jan Feb 11 D B Keele Jr Low Frequency Loudspeaker Assessment by Near field Sound Pressure Measurements J Audio Eng Soc 1974 April 12 W D T Davies Generation and properties of maximum length sequences Control 1966 J une J uly August 13 F J MacWilliams and N J A Sloane Pseudo random sequences and arrays Proc IEEE 1976 December 14 M R Schroeder Integrated impulse method measuring sound decay without using impulses J Acoust Soc Am 1979 August 15 J Borish and J B Angell An efficient algorithm for measuring the impulse response using pseudorandom noise J Audio Eng Soc 1983 July August 16 D D Rife Maximum length sequences optimize PC based linear system analysis Pers Eng Inst News 1987 May 17 C Dunn and M O Hawksford Distortion Immunity of MLS Derived Impulse Response Measurements J Audio Eng Soc 1993 May 18 R H Small Direct Radiator Loudspeaker System Analysis J Audio Eng
40. 20k Figure 11 6 Users should use this graphic to determine the lowest Frequency that has been measured in anechoic state Using a fixed predefined Microphone and Loudspeaker location makes all these parameters easier to define in routine measurement processes But for new situation its very advisable to run an MLS and have a look at the impulse response obtained Fig 11 7 shows the labels of the corresponding data to be input as gating parameters 0 020 Y 0 016 0 012 Figure 11 7 Chapter 11 Sinusoidal 113 11 4 DISTORTI ON AND SETTINGS Sinusoidal stimuli allows CLI O to evaluated distortion in its single harmonic contribution If not Setin Impedance Mode CLIO always evaluate harmonics from second to fifth and allows display each one separately via its own push buttons While it is straight to have meaningful distortion figure of electrical devices measuring Loudspeaker distortion in normal environments without anechoic chamber is not trivial We will give only some advise here relaying on examples as the topic is far beyond the scope of this User Manual To do this we will use CLIO s FFT Menu in quite an advanced way Distortion evaluation Is adversely affected by several parameters Two are the most important Noise 50 dBSPL of ambience noise a common figure usually does not affect Amplitude evaluation which is usually carried out at an average level of 90dBSPL This is particularly true using CLIO Sinusoidal Analysis c
41. 3 7 SYSTEM CALIBRATION This section describes how to perform the system calibration Be sure that any time you perform a calibration the system has warmed up for at least 15 20 minutes Leave the CLI O Box front plugs unconnected Select Calibration from the File menu 6 3 5 answer yes to the initial prompt this willrun an automatic procedure that will last several minutes The calibration procedure is completely automatic and several progress indicators will accompany all the executed measurements At the end of it your CLIO system should be calibrated and ready to carry out Measurements Progress indicator EX Proceeding with MLS Calibration This Step will take about 5 sec Atthe end of the calibration process it is always mandatory to verify the calibration itself this Is done by two simple measurements as described in the following section Chapter 3 Installation 33 3 7 1 CALI BRATION VALI DATI ON CLIO ELECTRICAL amp ACOUSTICAL TESTS _ O x File Analysis Controls Window Help 424 MR vets amp Di aw Ge OB a ww Py gh Mon i yA DO JCHA sl 2 Unsmoothed DI EQ Sinusoidal Qi E Ww JE L_L_L_ IITITOWTO _L__L__ I T WT W A _ Lt_L_L_L _ i Filename CHA dB Unsmoothed Stepped Delay ms 0 000 Dist Rise dB 30 y Figure 3 29 To verify the calibration first check that the generator output level is set to OdBu refer to 5 4 3 for details Press the channel A In Out Loop
42. 55 6 SYSTEM OPERATIONS AND SETTINGS eri 57 o INTRODUCTION WE 57 62 REGISTERED FILE EXTENSIONS ripis 57 6 3 FILE MENU AND MAIN TOOLBAR BUTTONS pre 58 6 3 1 LOADING AND SAVING E RE 58 SECH PRIN TIN alia E 60 EE e Eeer 60 0 34 EA POR ING GRAP RIO ina 61 00 CALI ATON EE 62 SEI UE e E E bac pemslae Napedent ea etesrsartentiptecra tease 62 6 3 7 STARTUP OPTIONS AND GLOBAL SETTINGS iii 64 6 3 8 SAVING MEASUREMENT SETTINGS sane 64 7 COMMON MEASUREMENT INTERFACE 65 Fer RICH Tel DUCTION aiar 65 7 2 UNDERSTANDING THE DISPLAY IN FRONT OF YOU ea 65 ET EE Eegenen 66 TARON EE ica 66 7 5 e t 66 7 6 THE MLS TIME DOMAIN DISPLAY eege 68 O MULIEMEIER Gato ii 69 ANTO PIGION coi ai 69 C2MULI NEERCONIROLPANE Lia 69 0 21 TOOLBAR eene 70 8 2 2 TOOLBAR DROP DOWN Ee 70 8 3 USING THE ORT RE CO E 70 Sd CONTROLLING THE GENERATOR ig e 70 0RZIHENNINEZEDS Rel a 71 8 3 3 CAPTURING THE GLOBAL REFERENCE LEVEL secccesccssesacseascqncntanecssauuseaemetempansceianss 72 6 4 THE SOUND LEVYELMETER E 73 8 4 1 CAPTURING THE MICROPHONE SENSITIVITY ssa age 73 So THE LOR METER Geni 74 620 MEASURING ANINDOUCGTOR EE 74 8 6 INTERACTION BETWEEN THE MULTI METER AND FFT 0 i iii 75 9 FFT AND RTA ieri eee 77 JT DATRODJO TION saer E E E E E 71 S2FFICONTROLPANEL ie nane ani 71 92 4 IVOLBARBULIONS sie po ire 78 9 2 2 TOOLBAR DROP DOWN LISTS AND DISPLAY ii 78 SskeroErriNnG5DIREOG EE 79 SAF FIANDRITAOPERMION Lean 80 E
43. 891 Tm 87 3024 0 0139 m 0 7827 mmiN 15 2204 g 15792 Oy 1 51E 7 men 78 86 kg m 8182 Qe 330 2142 uF 36 0777 H 79 1874 0 45437 Da 8 7699 CO 14 2936 g 7 7586 amp x 3559749 1849139 0 3238 14871 mH Loun 0 5961 mH Now we can Save our complete results and proceed with the Delta Compliance The free air derived data are already in memory and we can deal with the last part of the procedure only which is nearly the same as before We will be prompted for volume instead of weight Obviously the file we have to choose is relative to the driver loaded with a known volume 15 1 liters in this case Here we show the results for the delta compliance method The two sets of data do agree pretty well E Thiele amp Small Parameters Mil x ti g Fiba M MSE Manufacturer Example Models Date 06 0 7 01 F 46 1108 Hz Vas 23 8935L R 641008 Que 2 7924 Qe 0 6132 Qe 0 5028 Bl 6 3793 Tm dan 87 8432 So 0 0139 m Cys 0 8865 mmm Mus 1343810 Rus 13943 Qy as lear E F moh las 64 62 kgm Rae DER bla Cee 8302140 uF Lues 36 0777H Ree 2918740 Rar 40116 Qe Ee ies Mio 1251130 Zum 775869 Zax 3559740 Zaye 184913 2 Tio LU 2D bag 4671 mH out 0 5967 mH 13 7 4 USING MSE MINIMUM SQUARE ERROR With this option checked TS parameters are calculated in a more sophisticated way Basically the parameters obtained in the standard way are used to derive the starting values for the equivalent electric circuit model These values are then changed sli
44. AX TO US CLIO SERIAL NUMBER SOFIWARE VERSION PURCHASE DATE Chapter 1 Introduction 11 12 Chapter 1 Introduction 2 THE CLIO SYSTEM Depending on the hardware options that have been purchased the CLIO system consists of the following components The PB 4281 PC board and SC 01 signal conditioner The MIC 01 or MIC 02 also Lite microphones The PRE 01 microphone preamplifier The ClioQC Amplifier amp Switch Box Inthe next few pages we will describe each component and give its respective technical specifications NOTE Audiomatica reserves the right to modify the following specifications without notice Chapter 2 The CLI O System 13 2 1 THE PB 4281 PC BOARD AND SC 01 SIGNAL CONDITIONER The PB 4281 PC board and SC 01 Signal Conditioner form a high precision two channels A D D A audio front end for your IBM or compatible PC The PB 4281 PC board is housed in a standard PCI slot inside your computer and performs precise 18 bit digitizing of the signals to be analyzed The SC 01 Signal Conditioner is software controlled via an RS 232 serial link it is equipped with an instrument grade input and output analog circuitry with an exceptionally wide range of output attenuation and input gain that allows an easy interface to the outer world the input and output loopback capability with the internal ultra stable voltage reference permit a simple and precise calibration of the whole instrument the two
45. CAL amp ACOUSTICAL TESTS Iof File Analysis Controls Window Help SEAS slk v 5 ag ww GY ne a e ae E Br n a Measurement control V Generator control Input control In Out loop Phantom control re Output level Input sensitivity QUO Internal temperatu Autoscale Figure 5 2 CLIOwin Desktop Inside the main toolbar you may locate several distinct functional area starting from left to right we have file and print functions the measurement control the generator control and display of the output level the input control and display of input sensitivity the control for external hardware ClioQC Amplifier amp SwitchBox etc Follows a description of all the controls inside the main toolbar Refer to Section 5 6 for a detailed view inside the main menu 5 4 MAIN TOOLBAR Please refer to Chapter 6 for information about file and print functions 5 4 1 MEASUREMENT CONTROL Clicking on these toolbar buttons it is possible to interact and display each measurement control panel ifthe control panel is closed then it will be initialized and shown otherwise it will be simply activated in respect to the previously active one which will be deactivated The same functionality will be obtained with the relative shortcuts or Making a selection inside the Analysis Menu see 5 6 2 a third way is to select a window through the Windows Menu see 5 6 4 Enters the MLS Analysis control panel SS Enters the Waterfall control p
46. DWARE INSTALLATION aaa 19 3 21 INSTALCLUNG THE e e D era n 19 3 2 2 CONNECTING THE SC 01 SIGNAL CONDITIONER pini 19 3 3 HARDWARE REGISTRATION WITH WINDOWS cece cece eee e ee eeee erent ee eeaaaaaaaeeeeeeeees 22 3 3 1 HARDWARE REGISTRATION UNDER WINDOWS OX 0 cc i 22 3 3 2 HARDWARE REGISTRATION UNDER WINDOWS 2000 24 3 3 3 HARDWARE REGISTRATION UNDER WINDOWS XP i 26 3 3 4 IMPORTANT ADVICE E 29 34 SOFTWARE e LEE EE 30 OS THE EE neren 31 3 6 RUNNING CLIOWIN FOR THE FRESE IME lei 32 Se CC RN WS OI SE 32 3 7 S4 o IEMCALIBRATON greca 33 3 7 1 CALIBRATION VALIDATION aiar 34 3 8 CLIO SERIAL NUMBER AND DEMO EI E 35 4 TROUBLESHOOTING CLIO INSTALLATION 37 SGLIOWIN BASIO oe sincerest cise eens iii 39 ome H STT RTE 63910 Peete en ee i e ia E 39 IL OETANG E E 39 SLOW E eege 40 SM gt AINTOOLbA EE 40 5 4 1 MERSUREMNENECONIROL ici 40 54 2 INPUTOUFFEFLOOPBAC A ine 41 54 GENERATOR CONTROL EE 41 54A MN AE CONTROL E 43 S4 S MOROP e EK Ee CH EE 43 SE Ee 44 5 5 EXTERNALHARDWARE CONTROL gege 45 5 5 1 CONTROLLING THE CLIOQC AMPLIFIER amp SWITCHBOX aasssssssosssssnssnssrrrrssessrnnenes 45 5 592 CONTROLLING A TURNTABLE carie 46 5 6 MAIN MENU AND SHORTCUTS rai 47 SOA FEE MENG EE 47 5 6 2 ANALYSIS MENU iii aio 48 20o CONTROLS MENU tee 51 KOA WINDOW gt MENU E 52 Sb RELF MENU BEE 52 5 7 eher LE 53 5 COMNEGTING THE Ee 53 5 7 2 CONNEC TING TE E el 54 5 7 3 CONNECTING THE CLIOQC AMPLIFIERGOWITCHBOX isa
47. E EE E WEE 82 9 6 TIME DATA DISPLAY OSCILLOSCOPE li iii 84 OF Tir TAINS EI GAY einen ci iter 84 ef 85 est zer gl Eed HON ln 85 10 2 Ode Re TE MH 85 10 21 TOOLBAR BIN LE 86 10 2 2 TOOLBAR DROP DOWN LISTS eresie dae io 86 Eet Eege 87 10 24 MLS POST PROCESSING TOOLS aac 88 10 4 IMPULSE RESPONSE GONITAROLPANEL sciopero etere 89 10 4 1 TOOLBAR BUTTONS iii 89 10 4 MEASURING FREQUENCY RESPONSE Lalli 90 104 1 MEASUREMENT LEVEL Lena inan 90 1A MES REA 90 10 4 3 ACOUSTIC FREQUENCY RESPONSE ii 92 1044 PHASE amp GROUP DELAY EE 96 10 5 OTHER TIME DOMAIN INFORMATION WE 100 10 0PROGESSIN OOESBCXEXRMPLE aio 101 11 SINUSOIDAL EE 105 BSA TN VIP OD GOIN E 105 1 25INUSOIDALCONTROLEANEE cl 105 RR IOOLBARBUFIONS leali nt 106 10 2 2 TOOL BAR DROP DOWNS oe eo n SER O IR II 106 11 2 3 SINUSOIDAL SETTINGS DIALOG cccccccceeecceeeeeseeeeseeeeseeeesseeeesaeeesaeeeesaaees 107 11 2 4 SINUSOIDAL POST PROCESSING TOOLS ira 109 de ECHT Eege 110 13 1 STEPPED VS NOT SEENEN 110 11 3 2 FREQUENCY ee E ERR ciare 111 TS GATING aa 112 tI RI AR IN BIEN NEEN 114 12 WATERFALL sssssssssssssossssssssssesseesseessessseessessssessseesstesneeaneesneesneesses 117 AAAI CPOE UG THON EEN 117 I2 2WAIERFALLOONTROLPANEL lenire eni 117 122 1 TOOLBAR BUTTONS ee 117 123 WATERFALL BASIO S serieren ERE ee Oe eee ne eee eee en 118 12 3 1 CSD AND ETF MODES SETTINGS AND OPERATION E 118 12 3 2 FILE DISPLAY MODE SETTINGS AND OPERATION pi
48. MPULSE NEGATIVE MAPINK1024 ALL4096 SIG oi KBJIMPULSE POSITIVE Minne SET cancel Sianal ties sg 2 Z li Opens the output DC voltage control panel Output DC Control x EI Clio 100 QcBox U UM o RN E With this control panel it is possible to manage the DC voltage that the SC 01 signal conditioner is capable of superimposing to the signal generated by channel A output 42 Chapter 5 CLIOwin basics This DC voltage ranges from 2 5V to 2 5V at SC 01 channel A output as you may set with the slider Note if you feed channel A output to a DC coupled amplifier like the CLIOQC Amplifier amp SwitchBox the DC voltage that you will see at the amplifier s output will be multiplied by its gain This is why the control panel also displays the calculated DC voltage present at the QCBox output the calculation takes into account the QCBox type selected in the External Hardware control see 5 5 1 For example the DC voltage that may be present at the output of the QCBox Model 4 ranges from 25V to 25V With the Set DC button it is possible to activate the desired DC When DC Is active the control panel button becomes red BS to signal this particular state as in figure below The small Zero DC button lets you immediately reset the output DC to OV ER 10 0 de a e di DB a Output DE Control Pay great attention when driving loudspeakers with signals with DC present 5 4 4 INPUT CONTROL input sensiti
49. NT SETTINGS Measurements settings can be saved from within the MLS FFT Sinusoidal and Waterfall menu to do this simply check the Save Settings box in the Settings dialog of each menu Fig 6 10 refer to chapters 9 10 11 and 12 for details on settings VK Save Settings Defaut Cancel Fig 6 10 Save Settings check box Settings are saved in the mlspci stp MLS sinpci stp Sinusoidal fftpci stp FFT and wtfpci stp Waterfall files inside the installation directory Upon finding one of these files CLI Owin will reset the corresponding menu to the saved settings 64 Chapter 6 System Operations and Settings 7 COMMON MEASUREMENT INTERFACE 7 1 INTRODUCTION This chapter deals with the graphical user interface which is used to display and manage the measured curves within all CLIOwin frequency measurement menu In particular this Common Measurement Interface CMI is used by the FFT MLS and Sinusoidal menu The understanding of CMI behavior and capabilities is very important to use CLI Owin at its best 7 2 UNDERSTANDING THE DISPLAY IN FRONT OF YOU Fig 7 1 explains the main objects found in a frequency response measurement display Active Curve 2 oom Overlays ar xr D p gamigarc WI 110 0 180 0 Active na S468 AHIS HIN Si Y Scale 900 LC 76 0 Scale amp ctve Inactive 36 0 Zi SE 20 100 237 77 H ae ency scale Figure 7 1 Inside the graph you find the active curve which reflects an
50. SETUP File gt Setup This option gives you access to the setup dialog Fig 6 7 where you can define the following Screen Colors Print and graphics export colors Screen line width Print and graphics export line width The Company Name which will appear in all printouts CLIO Setup EN Colors Lines Company Mame Hardware Background EB Text a Color Scheme D Large Text D Bar graph Si Bi QC upper limit A E OC lower lirit E Overlay 3 i QC bad Bi E a Grid Mam Curve Overlay 1 Overlay 2 QC bad text DB UL good DI Default QC good text oi Overlay 4 Overlay 5 Marker Cancel Fig 6 7 Setup dialog 62 Chapter 6 System Operations and Settings Apart from the Default color scheme which is not changeable it is possible to define up to 5 color schemes User1 User2 User3 User4 and Printing The Printing color scheme as the name implies will affect your printouts and exported graphic files and if selected will let you preview on your screen how they appear When defining a color scheme you may press the default button which will load the Default scheme for your reference File gt Setup gt Hardware From this tab Fig 6 8 it is possible to select the serial port used to control your CLIO Box CLIO PB4281 o E nihi 2 gi pe Enpi Fig 6 8 File gt Setup gt QC From this tab Fig 6 9 itis possible to select the serial port used inside QC to c
51. STICAL TESTS File Analysis Controls Window Help ar AS MR mH LOOP a v A ORY a v A r ee NB SH Mall gt ole gt D n ac Dr ELECTRICAL amp ACOUSTICAL TESTS CLIOwin User s Manual ersio e 6 89 x 10 51 in Figure 5 1 CLIOwin Help On Line To request the CLI Owin on line help press F1 The on line help screen Fig 5 1 should appear and the context sensitive search should locate the page appropriate to the currently active menu dialog or control Note in order for the CLI Owin help to work you should have installed Adobe Acrobat Reader ver 4 or later in your system The CLIOwin CD ROM contains a correct version of this utility Refer to Adobe www adobe com for any ulterior information The CLI Owin help can be invoked also from outside CLI Owin to do this go to the Start Menu then Programs then Cliowin and then click on CLI Owin Help in this way Acrobat will let you read and print this User s Manual If you are not familiar with Acrobat please spend some time to familiarize with its capabilities controls and navigation buttons Another way to obtain help is through the Help Menu see 5 6 5 which gives you the possibility to view also the on line resources available in the Audiomatica and CLI Owin websites Chapter 5 CLI Owin basics 39 5 3 CLIOWI N DESKTOP The CLI Owin desktop presents itself as in Fig 5 2 and gives you access to the main menu and the main toolbar Ge CLIO ELECTRI
52. The last enemy we consider are external vibrations 130 Chapter 13 Measuring impedance and T amp S parameters Figure 13 8 Fig 13 8 IS an impedance curve taken with the loudspeaker disposed on a computer table on one of those appendices that may be set up or down upon needs This stuff clearly resonates exited by the loudspeaker around 200Hz No matter how good the loudspeaker is fixed to a structure if this does move by itself Usually there is no need to fix anything as long as you are using a stable non resonating structure Up to now we dealt with Internal Mode We will briefly go trough the others modes problems found up to here will remain the same or worsen from here on Chapter 13 Measuring impedance and T amp S parameters 131 13 41 SENSE Requires Audiomatica CLIOQC Amplifier and Switch Box model 2 3 or 4 It is a simplified Constant Voltage method Simplification arises as both device gain and sensing resistor around 0 1 Ohm is known Fig 13 9 shows the CLIOQC Software Control Dialog Box Sense should be selected ae Ier CLIQQC Amplifier amp Switch Box Controls Input C Input C Input 2 Input Cut A pene Input 8 Imp Internal D EN Type Sense A Ohm Model 2 0 127 Figure 13 9 Fig 13 10 shows required connections LPT PORT CLIOQC AMPLIFIER a
53. acement of the speakers in a listening room to the overall sound quality of a car stereo system In these case it is often used the pink noise as stimulus If you are not using CLIO as the source of such a stimulus be sure to use a good one you may 80 Chapter 9 FFT find several audio generators that do the job but they are usually expensive a good choice is to use a recorded tracks of one fo the various test CDs available in this case not all the CD ROM readers may furnish adequate results as appears from the graph in Fig 9 3 0 0 dBV 20 0 40 0 60 0 80 0 i Figure 9 3 All three graphs represent true analog pink noises they are played at 5dB different level for clarity The upper red is the output of an Audio Precision System One generator the second blue is the pink noise of track 4 of the Stereophile Test CD played by a Philips CD692 CD player the third is the same track of the same test CD output by the computer where l m writing right now Pioneer DVD Player plus Crystal Sound Fusion PCI Audio When taking RTA measurements use at least 16K FFT size if you want to cover the entire 20 20kHz audio band using lower sizes results in octave bands not present as no FFT bins fall inside them Chapter 9 FFT 81 9 5 AVERAGI NG Averaging plays a very important role in FFT and RTA analysis It is vital when analyzing signals buried with noise It is also Important when taking spatially averaged me
54. anel ly Enters the FFT Analysis control panel o Enters the Sinusoidal Analysis control panel tx Enters the Multimeter control panel Tg Enters the Thiele amp Small Parameters control panel H Enter the Quality Control Processor 40 Chapter 5 CLIOwin basics 5 4 2 INPUT OUTPUT LOOPBACK The CLIO Box features an internal loopback very useful for performing self tests Connects channel A output to channel A input with an internal relay HConnects channel B output to channel B input with an internal relay 5 4 3 GENERATOR CONTROL CLI O s generator can be controlled from the dedicated toolbar buttons and dialogs another powerful way to manage it interactively with a level measurement is from within the Multi meter control panel which can be invoked with the F4 shortcut Refer to section 8 3 1 for details output level display amp control buttons Displays the actual output level in dBu of the internal generator This level is valid for both output channels It is possible to modify it in 1dB steps pressing the or F7 and a or F8 buttons Ifthe Shift key is pressed simultaneously then the steps are of 0 1dB dj Switches on and off the generator To immediately kill the generator it is possible to use the ESC key If you wish to receive a message Fig 5 3 before playing check PromptOnPlay in the generator drop down menu see right below Clicking on the small arrow aside the button the generator drop down menu is
55. ano 119 12 4 MAKING A CUMULATIVE SPECTRAL DECAY 120 12 5 MEASURING AND REPRESENTING LOUDSPEAKER POLAR DATA 123 12 5 1 PREPARING THE MESCONTROLPANEL cca elio nt 123 12 5 2 PREPARING THE TURNTABLE E 123 12 5 3 TAKING THE MEASUREMENTS ii renna 124 12 5 4 REPRESENTING POLAR DATA WITH A WATERFALL u cece eccceceeseeeeeeee eee eees 124 13 MEASURING IMPEDANCE AND T amp S PARAMETERS 127 CECR Ee Reg EEN 127 E EE Ee EE 127 SS INTERNAELMODE E 127 13 3 1 MEASURING IMPEDANCE OF LOUDSPEAKERS un 128 i 2SETtTINGTHERICATEEVEL aaa 129 13 3 3 DEALING WITH ENVIRONMENTAL NOISE criar arde 130 13 3 4 DEALING WITH VIBRATIONS seet ee 130 PANE e TI riti 132 13 5 CONSTANT VOLTAGE amp CONSTANT CURRENT Mirren 133 E ONIN EA 133 13 5 2 CONSTANT CURRENT WEE 135 13 oC IMPEDANCE SINUSOIDAL e dE 136 13 7 THIELE amp SMALL IEN co ia 138 T7 INTRODUCTION E 138 13 7 2 T amp S PARAMETERS CONTROLRANEI eeaesuesaesaeseeeeeeeeeeaeeaneas 138 13 73 GLOSSARY OF SYMBOLS ebe 139 E ee aad eco er Berd all CN STEP EE 140 13 7 4 USING MSE MINIMUM SQUARE ERRDOR 142 SEIL le Ah GE 143 1INTRODUCTION 1 1 ABOUT THIS MANUAL This User s Manual explains the CLIO system hardware and CLI Owin software All software versions are covered please note that CLI Owin software is designed to operate in conjunction with the supplied hardware If this hardware is absent or the serial numbers do no
56. apability which by means of DSP filtering allows exceptional S N Ratio Unfortunately evaluating 1 distortion means looking for signals that are 40dB lower than the 90dBSPL mentioned above in the same magnitude order of environment noise Gating Effects Device settling time not perfect delay removal and reflections arriving within the Sampling time Meter On seriously affect distortion measurements creating artifacts Itis advisable to perform a noise evaluation using FFT Analysis Fig 9 shows two curves the first red is obtained with the Max Hold function the second black with Min Hold Figure 11 8 The first a sort of worst case should be taken as the reference lower distortion floor once risen 10dB at least The second is useful to identify pure tones in the noise spectrum these are likely to produce both distortion increase as well as cancellation artifacts In our case this tones are caused by more than 20 different computer fans Spread everywhere in the room Supposing we carry a distortion analysis at an average 90dBSPL residues below 1 are difficult to evaluate up to 600Hz things going much better at higher frequencies Remember that the frequency axis should be referred to the harmonic we are looking for not to the fundamental The obvious solution
57. apter 13 for details LPT PORT CLIOQC AMPLIFIER amp SWITCHBOX SENSE FROM CLIO INPUT 1 INPUT 2 GAIN 10dB Model 1 283 INPUTN o GAIN 20dB Model 4 Figure 5 25 Chapter 5 CLIOwin basics 55 56 Chapter 5 CLI Owin basics 6 SYSTEM OPERATI ONS AND SETTINGS 6 1 INTRODUCTION This chapter completes the introduction to CLIOwin started in Chapter 5 Here you will find information about Files extensions File operations Printing Exporting data Exporting graphics Calibration of CLIO Software setup Startup options Measurements settings 6 2 REGISTERED FILE EXTENSIONS CLI Owin registers during its installation several file extensions which will let you easily find a file done during your work Browsing your hard disk you will then encounter the icons that we are going to describe mis MLS frequency response data files 43 2 MLS impedance data files MLS process files SZ I Waterfall data files RS FFT and RTA data files Sinusoidal frequency response data files Sinusoidal impedance data files Sinusoidal process files Multi meter data files T amp S parameters data files sia BE Be B Be Ba Signal files Chapter 6 System Operations and Settings 57 When you find a CLIOwin data file it is possible to invoke the program simply clicking on the file itself if CLIOwin is open it will load the file in the appropriate menu and display it if it is clos
58. asure ments CLIOwin has flexible averaging capabilities Averaging basically means adding and dividing for the number of additions made To start an averaged FFT measurement you need to set a number bigger than one in the Target Average drop down otherwise you have a continuously refreshing single measurement that will continue until the Stop button is pressed It is possible to choose between linear and exponential averaging The instrument behaves differently in the two averaging modes In linear averaging the measurement is continued until the target is reached then it automatically stops What you got is exactly what we just explained In exponential averaging the measurement never stops When the target is reached the averaging continues relying on a mathematical formula which discards the oldest acquisitions and gives more and more importance to newer ones The exponential averaging is the default one As an example Fig 9 4 compares a single 1kHz sinusoid FFT analysis and 100 averages one CLIO 120 0 Wat il wt RR Dit Mai vg d ott ul d 120 0 150 0 150 0 0 00 2000 4000 6000 8000 10000 12000 14000 16000 Hz 18000 20000 0 00 2000 4000 6000 8000 10000 12000 14000 16000 Hz 18000 20000 Figure 9 4 This is a classical example of signal buried with noise the sinusoid s 9th harmonic is clearly visible after 100 averages but invisible for a single ac
59. ation is in the time domain here this approach in our opinion greatly simplifies a step by step approach In fact user can at first completely ignore most of the settings we encountered in the previous paragraphs and get the most intuitive piece of information that is the Frequency Response of a device under test Our first step will be measuring the response of an A weighting filter All the settings are left in their default state we will take care on measuring level only Ours is not a power device is not a loudspeaker so we think it cannot be damaged with an output set to 0dB 5 21dBV with Mls signals We connect CLIO output A with the device input CLIO Input A with the device output we enable input auto range and click the Go button As result we get Fig 10 5 108 0 180 0 20 100 1k Hz 10k 20k 20 100 1k Hz 10k 20k Figure 10 5 and 10 6 The curve reaches 16dBV 6 3V at 2 5kHz which is a quite high level for our device Looking for trouble we increase CLIO output to 6dB and measure again obtaining Fig 10 6 The device went into saturation in more emphatic terms it is not linear any more The whole MLS process works on the assumption the device is linear If this is not the case is not easy for inexperie
60. ble the information given here apply to the control of the Outline ET ST Turntable they can be adapted to any other device The turntable control is achieved with Bit 7 of the parallel port output bits as showed in Fig 5 6 The turntable should be connected to the parallel port of the computer by means of a cable defined as follows PC side DB25 male ET ST side DBI male Pin Y EE EE gt Pin 2 Pin 22 ssesaecensoreseseosce gt Pin 4 All other pins unconnected The cable should be connected as in the following figure Connecting cable to PC parallel port Fig 5 9 Outline ET ST Turntable connections Inside the Turntable control panel it is possible to set its Resolution in degrees and Speed in rotations per minute the combination of these settings give the software indication about how much time to wait after the controlling pulse is output We have two controlling buttons defined as follows Single Pulse Itis used to give a single manual triggering pulse to move the turntable to the next position Link To Measurement When pressed enables the software to move the turntable at the end of an executed measurement works only with the MLS and Sinusoidal control panels Refer to chapter 12 for an example of how to use this feature during polar measurements 46 Chapter 5 CLI Owin basics 5 6 MAI N MENU AND SHORTCUTS Read carefully this section which gives you a comprehensive list of all the menu and Shortcuts active with
61. cally repeated until the users presses a keystroke or releases the button If Autosave is active the loop mode ends after the total files to be autosaved are done When an MLS measurement is taken automatically applies the selected post process Enters the MLS settings dialog box Enters Time domain Enters Frequency domain dh Displays phase f 3 Displays group delay 10 2 2 TOOLBAR DROP DOWN LISTS input channel Selects the input channel configuration Y scale unit Selects the measurement units It is possible to select Voltage dBV dBu dBRel or Pressure dBSPL or Impedance Ohm smoothing Activates a frequency smoothing of the active curve This smoothing effect will al low for a better appreciation of the general features of the response curve The Smoothing algorithm that is employed averages all values within a fraction of octave band surrounding each analysis frequency 86 Chapter 10 MLS 10 2 3 MLS SETTI NGS DI ALOG General Sampling Lan E 16k ni Stimuli S ZE Ce Continuos Window Rectangular C Impulse Manual Phase amp Group Delay Impedance CG Normal Ce Internal Minimum h Wrapped OC Bos Sense Excess Save Settings i Default Cancel Figure 10 2 sampling Selects the measurement sampling frequency size Selects the size of the MLS sequence window Selects the appropriate kind of window for analyzing time
62. can add subtract multiply and divide the data in memory either wit a single complex value or with a compatible file Compatible means that it must be a file with the same basic settings as the one in memory Y scale must also be the same that is you cannot add dBV with Ohm The use Load Process and Save Process will become clearer along the examples The Add and Sub functions are most used among files We will use them to obtain the sum and difference of the woofer and tweeter of Fig 10 20 Results are in Fig 10 30 where the sum is in red and the difference in blue This are useful plots to start with during a cross over design Interesting enough is the big notch in the sum curve something not easy to imagine from the magnitude response 110 0 CLIO 180 0 dBSPL Deg 100 0 108 0 70 0 i 108 0 60 0 180 0 20 100 1k Hz 10k 20k Figure 10 30 The divide function in its most classical use allows to show a magnitude response as transfer function with another measurement Suppose you want to evaluate how the grid affects the frequency response We will use as reference the response of Fig 10 17 which has been taken with the grid in place We remove it take another measurement and perform a division by file with the grid in place We remove it take another measurement and perform a division by file with the data of the reference Result
63. cribed in detail below It is the heart of the whole menu and should be thoroughly understood before pressing Go Displays second harmonic distortion risen the amount of dB defined in the Setting Dialog Display third harmonic distortion risen the amount of dB defined in the Setting Dialog Display fourth harmonic distortion risen the amount of dB defined in the Setting Dialog Display fifth harmonic distortion risen the amount of dB defined in the Setting Dialog All the distortion buttons are disabled when Ohm is selected as y scale unit 10 2 2 TOOL BAR DROP DOWNS input channel Selects the input channel configuration See 5 6 for details Y Scale units Selects the measurement Y scale unit Possible choices are dBV dBu dBRel as Voltage units dBSPL as pressure unit Ohm as impedance unit dBV and dBu refer the 0 dB on the scale to 1 V and 0 775 V respectively dBrel refers the 0 dB on the scale to the value set within the MULTI METER dBSPL switches the system to work in pressure mode A conversion from Volts to Pressure is accomplished based on the Microphone sensitivity set in the dedicated Dialog Once the measure is taken the conversion is done and all the internal data are stored in Pressure This means that further changes to Microphone sensitivity do not affect in memory or saved measurements Ohm switches the system to convert the measurements in Ohm basing the conversion on the Impedance Mode Settings available in
64. d are described with examples and figures to the Windows 98 operating system English version they can be applied with only minor modifications and appropriate translations to all languages and to Windows 95 or Windows Me Let s now switch the PC on As soon as Windows is started the Add New Hardware Wizard automatically detects the CLIO card Figure 3 6 You will then be prompted with the dialog boxes in Fig 3 7 Press Next and then select Search for the best driver for your device Recommended Add New Hardware Wizard Add New Hardware Wizard Figure 3 7 22 Chapter 3 Installation At the successive prompt Select Specify a location then insert the CLI Owin CD ROM in the CD ROM drive and press the Browse button Choose the CLIOPCI INF file inside the INF directory inside the CD ROM see Fig 3 8 Add New Hardware Wizard Add New Hardware Wizard Windows will search for new drivers in its driver database Windows driver file search for the device on your hard drive and in any of the following selected locations Click Next to start the search TT Floppy disk drives CLIO PB4281 PCI Audio Windows is now ready to install the best driver for this device Click Back to select a different driver or click Next to continue I CD ROM drive TT Microsoft windows Update Location of driver IV Specify a location IM DI DIMNFACLIOPCI INF Figure 3 8 You should now be prompted by
65. d the selected file to obtain a constant current impedance measurement Both files should be in dBV ei Combines the actual measurement and the selected file to obtain a constant voltage impedance measurement Both files should be in dBV 88 Chapter 10 MLS 10 4 I MPULSE RESPONSE CONTROL PANEL ES MLS Impulse Response O x deo SSL A E Ski fav funs x 0 00 32 64 96 128 160 192 224 256 ms 288 320 Filename CHA dB Unsmoothed 51 2kHz 16K Rectangular Z Figure 10 4 10 4 1 TOOLBAR BUTTONS The following toolbar buttons differ from frequency domain control panel Displays Impulse Response Displays Step Response Displays Schroeder Decay G Displays Energy Time Curve ETC Also the following buttons inside the measurement area are peculiar of this control panel See Chapter 7 for other information i Selects the starting point of the measurement window Selects the end point of the measurement window Restores the default state of the measurement window thus selecting all the acquired points for analysis Chapter 10 MLS 89 10 4 MEASURI NG FREQUENCY RESPONSE In a step by step process we will deal with any single aspect that affects MLS measurements results At first we deal with electrical measurements leaving acoustical as the last steps 10 4 1 MEASUREMENT LEVEL Opening the MLS menu for the first time you will see a graph which has frequency on its X axis Despite the mother of all inform
66. data It is possible to select between a rectangular Hanning or Blackman window the last two can be full or half sized NOTE These windows are applied to the time portion to be transformed with FFT If the start point is near the impulse full windows will null the most important part of the time response due to their rise time To evaluate the effetcs of a data window refer also to Chapter 9 and FFT measurements in general stimull Selects the kind of stimulus used for the measurement of the impulse response averages Controls the averaging mode of operation The measurement will be repeated and averaged the number of times set therefore obtaining a better signal to noise ratio at the expense of reduced measurement speed Continuous performs the number of averages in the shortest time without waiting Manual waits the user to press any key between each measure it is useful for example in averaging different microphone positions phase amp group delay Used to select how phase group delay response is obtained Normal displays the measured phase group delay curve referring to the selected time domain data Minimum calculates and displays the phase group delay curve related to the current modulus curve in the assumption of minimum phase behaviour i e the Hilbert transform of the log magnitude Excess calculates and displays the phase group delay curve as the difference between the Normal and the Minimum ones It is possible t
67. de should the Time Shift value be left at zero the routine will automatically calculate it soacing the selected Number of Spectra in the interval defined by start and stop times if Time Shift is forced by the user be sure to set it small enough to permit the last spectra to be calculated if the fixed stop time is passed then the calculation defaults as in case of zero Time Shift When representing a CSD the program automatically hides the low frequency part of the spectra that has become unreliable due to the time frequency uncertainty principle ETF Energy Time Frequency is intended for room acoustic evaluation in this case all MLS data starting from the start time are computed then successive slices are calculated moving their initial point of the Time Shift value 12 3 2 FILE DISPLAY MODE SETTINGS AND OPERATION Root File Name and browse button Name of one file within the set to be displayed Pressing the associated button it is possible to browse the disk and choose the file Z Start Value associated to the first rearmost file Z Stop Value associated to the first foremost file Z Ref Value associated to the file to be taken as reference Start Frequency Start frequency of the waterfall Stop Frequency Stop frequency of the waterfall File display mode is a powerful way for synthesizing a large number of measurements in a single 3 D graph This mode allow the representation of the polar response of a loudspeaker
68. domain Equivalent to a And when in Frequency domain P Displays Phase Equivalent to d D Displays Group Delay Equivalent to E And when in Time domain I Displays Impulse Response Equivalent to A P Displays Step Response Equivalent to D Displays Schroeder Decay Equivalent to zx E Displays Energy Time Curve Equivalent to h ae CLIO ELECTRICAL amp ACOUSTICAL TESTS File Analysis Controls Window Help ce LU Mes Ctrl hd la we To 0 Waterfall Ga G lin EFT Dt Settings Sinusoidal Ctrl 5 Expand i Multi Meier F4 Compress To T amp S Parameters Cat Marker M Qo Quality Control Cf Fig 5 13 Waterfall Submenu G Starts a Waterfall processing Equivalent to Te S Enters the Settings dialog box Equivalent to dt M Invokes marker Equivalent to Gg ae CLIO ELECTRICAL amp ACOUSTICAL TESTS File Analysis Control Window Help ca IM mes Ch j N o SE Waterfall Cirle Lo I A Sinusoidal Ctrl S Continue x Multi Meter F4 Stop T k T amp S Parameters Ctrl T Hr Quality Control Dit Quality Control Ctrl Q Internal Trigger Time Data DI Hald H Settings Fig 5 14 FFT SubMenu G Starts an FFT measurement Equivalent to Te T Stops the FFT measurement Equivalent to I Sets the Internal Trigger mode Equivalent to IL D Invokes the Time Data display Equivalent to dba Chapter 5 CLI Owin basics 49 H Enables the Hold function Equivalent to pu S Enters the Settings dia
69. e Fast Fourier Transform hereafter FFT of the impulse response As the crucial piece of information is in the time domain MLS is particularly well suited for recovering the anechoic sound pressure response of a loudspeaker i e the frequency response of a loudspeaker as if it where positioned in an anechoic room while carrying out the measurement in a normal room Important as well MLS allows complete evaluation of room acoustic parameters Within this Menu user will be able to switch from time domain to frequency domain and backward using the powerful post processing tools CLIO gives This allows getting very sophisticated and complete information of any electro acoustic device Both the theory behind all this and the amount of parameters that affect the measurement results make this Menu probably the most complicate to use We will skip theory completely and after a concise description of whole User interface will deal with real life applications 10 2 MLS CONTROL PANEL Ba MLS Frequency Response O x ago zi allla 6 fora fev pef Unsmoothed zl qa DDSIDDRr SD 180 0 1k Hz 10k 20k GA 6 0 Filename CHA dBY Unsmoothed 51 2kHz 16K Rectangular Z Figure 10 1 Chapter 10 MLS 85 10 2 1 TOOLBAR BUTTONS fei Starts an MLS measurement K l pressed the measurements will be autosaved The current autosave definitions apply see 6 3 1 for details Selects the Loop mode When in Loop mode the MLS measurement Is automati
70. e Is very flat over the entire audio band no particular correction is usually needed 2 2 1 THE MI C 02 MICROPHONE The MI C 02 microphone is functionally identical to MI C 01 It differs only in the fact that its length is 12 cm instead 25 cm The MIC 02 is more practical to handle and to work with and is ideal for measurements in a reverberant environment 2 2 2 TECHNICAL SPECIFICATIONS MIC 01 Type Condenser electret Accuracy 1 dB 20 Hz to 10 kHz 2 dB 10 kHz to 20 KHz direct field Maximum level 130 dB SPL Dimensions 8 mm diameter 25 cm long Accessories wooden case 2 7 m cable stand adaptor MIC 02 Same as MIC 01 but 12 cm long Chapter 2 The CLI O System 15 2 2 3 THE MI C 01 OR MI C 02 FREQUENCY CALIBRATION DATA Free field Microphone 5 0 Type MIC 02 pi Calibration Chart 0 0 Serial No 9202011 Sensitivity 35 5 dBreiViPa 17 24 mvViPa Valid at 5 0 Temperature pa CG Ambienti Static Pressure 102 0 kPa Relative Unicity 47 e Frequency 1000 Hz 10 0 Polarization Conditions 22 50 V EOhm Reference Instruments MANUF MODEL SERIAL NO CALIE DATE HP 34084 s13a7A09881 20 06 2002 15 0 LARSON DAVIS 812 416 10 05 2002 BEK 4731 1759543 10 05 2002 PI 4039 2345012 05 03 2002 ag Date 10 15 2003 Certficate NO 9315 Signature M J Da 20 100 10k Hz 20k The microphones MIC 01 and MIC 02 can be furnished with or be submitted for a frequency calibration certificate This document alo
71. e procedures described refer specifically and are described with examples and figures to the Windows 2000 Professional operating system English version they can be applied with appropriate translations to all languages Let s now switch the PC on As soon as Windows is started the Found New Hardware Wizard automatically detects the CLIO card Found New Hardware Multimedia Audio Controller Figure 3 11 You will then be prompted with the dialog boxes in Fig 3 12 Press Next and then select Search for a suitable driver for my device Recommended Found New Hardware Wizard Found New Hardware Wizard Install Hardware Device Drivers Bra Welcome to the Found New 4 device driver is a software program that enables a hardware device to work with SS Hardware Wizard an operating system This wizard helps you install a device driver for a This wizard will complete the installation for this device hardware device oy Multimedia Audio Controller A device driver is a software program that makes a hardware device work Windows needs driver files for your new device To locate driver files and complete the installation click Next What do you want the wizard to do quaseneesezeeezazeznesazaazezaaeonesnazeonesIzanenaneenezenazenanenanasenaz zena nea zena nese nane ze nina e zena zena zena nera ne zena nane zenenea Display a list of the known drivers for this device so that can choose a specific driver
72. e to measure the speaker from 60 to 60 in intervals of 5 relative to its front baffle The MLS measurement should be set in a particular way in order to automatically acquire the responses at various horizontal angles To do this we will use the autosave function the loop mode and the link to the turntable control Let s start from setting the autosave function Pressing Alt F2 we recall the Autosave Setting dialog fig 12 10 here we input the desired filename rcf deg start 60 increment 5 and total 25 values AutoS ave Settings Ge bel Path IC ACLIOZ000 data Root File Name ICT deg Stark 50 0 Increment f Total Number 25 Figure 12 10 The MLS menu is now ready to start taking measurements we only need to properly set the turntable and its control 12 5 2 PREPARING THE TURNTABLE We consider that the Outline turntable is properly connected to your PC refer to 5 5 2 to have details To prepare for this measurement session you need to 1 Manually set the front selector labeled Deg Step to 5 2 Rotate counterclockwise the turntable until you reach the desired start position as we want to start from 60 position it at 300 3 Recall the turntable control dialog Fig 12 9 set Resolution at 5 Speed at 0 75 RPM and press Link To Measurement Chapter 12 Waterfall 123 External Hardware ale er E Turntable Controls LI Single Pulse 77 Link To Measurement
73. ed connections and operations In this mode the Multi meter takes control of the generator and when the measurement is started outputs a series of sinusoids of variable frequency in order to find the best one to carry out the measurement The output frequency can be displayed with the magnifier button together with the measured parameter 8 5 1 MEASURING AN INDUCTOR Measuring an inductor is as easy as connecting it as in Fig 8 9 slecting the In Out Loop with Aert and press Go The most critical factor influencing this test are connections as with all impedance measurements if you use pin to alligators cables put a great care in avoiding false contacts which may arise if terminals are oxidized or alligators loose their bite 74 Chapter 8 Multi Meter Dei CLIO i EN a a a ER TE A e Figure 8 9 In a few seconds the measure stabilizes to the final result shown in Fig 8 10 This was a 4 8H nominal inductor the panel shows also the test frequency that in this case IS 2510Hz The same procedure should be carried out when measuring resistors or capacitors Gu a Inductance DIr CHA ll z a es ZS I BC sil Zaid Mis VV PK FILE SET emaje afe Gelo Sola Pressure dBSPL 4 8 5 9 Voltage mi rms mH Frequency 2510 Hz Filename RUNNING E Figure 8 10 8 6 INTERACTION BETWEEN THE MULTI METER AND FFT The Multi meter uses the same capture and processing units as the FFT control panel
74. ed it will also be launched It is possible to run only a single instance of CLI Owin 6 3 FILE MENU AND MAIN TOOLBAR BUTTONS Fig 6 1 shows the File menu and the Export submenu Refer to 5 5 1 for the shortcuts active CLIO ELECTRICAL amp ACOUSTICAL TESTS File Analysis Controls Window Help gt Open F3 In a xx To Hr El Save be Autosave Alt F2 Notes Data Shift F2 Graphics Ctrl F2 EB Print Alt P IW Autoscale F6 Calibration Setup Exit Fig 6 1 File Menu 6 3 1 LOADING AND SAVI NG FI LES Ga Loads a measurement file relative to the active control panel It is important to note that it is possible to load more than one data file type from the following menu MLS loads frequency response files mls and impedance response files mlsi FFT loads FFT files fft and CLIO4 RTA files rta Sinusoidal loads frequency response files sin Impedance response files sini CLIO4 sinusoidal frequency response files frs and CLIO4 impedance response files imp You can select the desired file type from the Files of type drop down inside the Open dialog box al ole Look in data l E ER bose sub max _ demo ER bose sub min _ polar a bose sub norm _ rum ER esbneanwooter alma E seas 03mm alma vita Files of type Sinusoidal files sin sini Cancel Hi Fig 6 2 Open dialog az Saves a measurement file relative to the active contr
75. edance the second the impedance obtained either with Delta Mass or Delta Compliance method The first consists in adding a suitable Known Mass to the Loudspeaker cone the latter in loading the cone with a Known Volume 13 7 2 T amp S PARAMETERS CONTROL PANEL E Thiele amp Small Parameters Pe Es ti Fenaa MSE Manufacturer Date F 0 0000Hz Vag 0 0000 L R 0 00002 Que 0 0000 Qe 0 0000 Qe 0 0000 Bl 0 0000 Tm dan 0 0000 Sy 0 0000 m Cue 0 0000 mm N Ma 0 0000 g Das 0 0000 Sy Cas 0 0000 min Mas 0 0000 kg m Ras 000009 cia O00 Lees 0 0000 H Ree 0 0000 amp Rar 0000094 Du 0 0000 Sy Mio 0 0000 g Zum 00000 Zuax 0 0000 8 Zaye 0 0000 Hp 0 0000 wo Luut 0 0000 mH out 0 0000 mH H The User Interface is quite simple with three Buttons one Drop Down and one Check Box fei Starts a T amp S Parameters procedure See 13 7 3 for details a Delta mass T amp S Parameters calculation See 13 7 3 for details Si Delta compliance T amp S Parameters calculation See 13 7 3 for details The Drop Down allows selecting the data origin as described in the introduction The MSE Check Box when checked enables a Minimum Square Error routine while calculating TS Parameters more on this later Aside information regarding the device tested the Control Panel displays 27 parameters Here is what they are 138 Chapter 13 Measuring impedance and T amp S parameters 13 7 3 GLOSSARY OF SYMBOLS MT Resonant frequency
76. eferred to a common measuring ground When you are making measurements in the normal configuration channel A or B unbalanced one of the two measuring points MUST be at ground potential Problems may arise if one tries to use amplifiers with floating outputs the connection with CLIO could cause damage to such an amplifier Use the channel A B balanced connection in such cases Unless you are executing impedance measurements with the Internal Mode selected one of CLIO outputs will usually be connected to an external power amplifier that will drive the loudspeaker electronic apparatus or other system under test The output of the system under test will be connected to one of the CLIO Input Chapter 5 CLI Owin basics 53 5 7 2 CONNECTI NG A MI CROPHONE For acoustical measurements you will connect a microphone optionally followed by a preamplifier or power supply to CLI O s input channel When using a MI C 01 or MIC 02 microphone it is possible to connect it directly to CLI O s input remember in this case to switch the phantom voltage on pressing the phantom button Ty It is good practice to wait a few seconds before taking measurements as the microphone s output stabilizes If the measuring point is far from the PC always lengthen the connection between the preamplifier and CLIO Make sure that you never use microphone cable that is longer than the one that has been supplied In Fig 5 23 we see the typical test setup for perfo
77. ers value and the marker reading at 1kHz Example known resistor value 10 Ohm reading at 1kHz 9 3 ohm sense value 0 127 Ohm Multiply 0 127 by 1 075268817 obtain 0 13655914 input this new value and check everything performing a new measurement 13 5 CONSTANT VOLTAGE amp CONSTANT CURRENT These were the standard approaches to measure impedance with traditional set of instruments We will skip further theoretical discussion and go directly on how CLIO implements them These methods both require two external components a reference resistor of suitable and know value where known means better than 1 tolerance and a power amplifier They also require two measures to be taken one after the other changing connections in between CLIO by means of its processing tools can speed up things a lot but the whole procedure remains quite complicate Whatever you are going to use MLS or Sinusoidal all the measurement should be performed in Volts the Y Scale Should be dBV 13 5 1 CONSTANT VOLTAGE Proceeding step by step we are going to create two files one named reference the second named device The two measurement files must have identical settings and identical CLIO s output level We choose a sensing resistor Rs of 1 ohm 1 Fig 13 11 shows connections for creating the reference file The level you choose now is the total measuring level INPUT A INPUT B OUTPUT A OUTPUT B Figure 13 11 The reference measurement
78. es H E IDE ATA ATAPI controllers FAR Keyboards E Mice and other pointing devices aS Monitors Network adapters EF Ports COM amp LPT EE Sound video and game controllers i ch Audio Codecs i Lf CLIO PB4281 PCI Audio WDM i C Media CM8738 Audio Driver WDM Legacy Audio Drivers Lo Legacy Video Capture Devices tbl Media Control Devices i Video Codecs e BR System devices a Universal Serial Bus controllers My Computer Open Explore Search Manage Map Network Drive Disconnect Network Drive Create Shortcut Rename Properties Figure 3 15 The presence of the CLIO PB4281 PCI Audio WDM under Sound video and game controllers confirms the correct installation Chapter 3 Installation 25 3 3 3 HARDWARE REGISTRATION UNDER WINDOWS XP The procedures described refer specifically and are described with examples and figures to the Windows XP Professional operating system English version they can be applied with only minor modifications and appropriate translations to all languages and to Windows XP Home Let s now switch the PC on As soon as Windows is started the Found New Hardware Wizard automatically detects the CLIO card N JJ Found New Hardware EJ Recycle Bin Multimedia Audio Controller Figure 3 16 Windows XP is the only operating system that is able to install a driver for the CLIO card the problem is that it is not the correct one and needs to be updated
79. es have been typed in clicking Ok we will prompt for the file name The file required here is the free air Impedance measurement Look in IS Capl3 ES EA deltacomp 5 1 vibrations deltamass13g ifreesir internal ES noise 1 0 Files of type Impedance Files Cancel Z Opening the file we get this partially filled TS parameters screen EN Thiele amp Small Parameters ti d CO FileData MSE Manufacturer Example 46 1108 Hz Vas O OO00L 6 4100 0 2 7924 Oes 0 6132 0 5028 0 0000 T m dEsp 0 0000 0 0000 rr 0 0000 mr Mus 0 0000 g O OOOO Ou 0 00 r m Mas 0 00 kgim Oa 330 2142 uF Les 26 0777 H 29 1874 amp 00000 Ma Rit D 0000 Gy 0 0000 g 7 7586 2 Zig 2559140 fives 184913 0 O 0000 LakHz 14871 mH REIS 0 5961 mH E Now we can save this result for later use or proceed immediately for the missing parameters Notice that the two Buttons for Delta Mass and Delta compliance that were disabled before are now enabled We Click on the Delta Mass Button type in the required values T amp S Parametrs Input Diameter mm 133 Mass g j3 Cancel and finally after we have choose the impedance file obtained with the added mass we get our completely filled TS parameters screen Chapter 13 Measuring impedance and T amp S parameters 141 E Thiele amp Small Parameters Su dd FileData sl MSE Manufacturer Example Miel Es 46 1108 Hz 21 0957 L 6 4100 amp 2 924 0 6132 0 5025 6 7
80. executed or loaded from disk measurement up to five overlays curves which are stored by the user and can be switched on and off interactively the marker which is activated clicking with the mouse in the graph area Above the graph itself we find several buttons and checkboxes which divide in three main categories active curve zoom and overlays management Aside and below the graph we find the Y Scales the Frequency or Time Scale and Marker Indicators One of the two Y scales is of the same color of the active curve and refers to it The marker indicators give the user the reading of the active curve The objects described may from case to case not all be present at the same time as in the case of Time Data display in the FFT menu The frequency or time scale may be logarithmic or linear A particular representation is the MLS time domain which will be discussed later in 7 5 It is possible to have two graphs in the same control panel see FFT In this case one is referred as active after you have clicked on it To change the colors of the screen active curve and overlays refer to section 6 3 6 Chapter 7 Common Measuring I nterface 65 7 3 BUTTONS AND CHECKBOXES A Moves shifts the active curve upward Moves shifts the active curve downward Expands magnifies the active curve it also changes the Y scale respectively hd Ab 4 Compresses reduces the active curve it also changes the Y scale respectively Zoom
81. f the microphone would have been exactly in the acoustic centre of the driver The most obvious application is to furnish data to cross over CAD Chapter 10 MLS 99 10 5 OTHER TIME DOMAI N INFORMATI ON CLI O gives aside the impulse response we already dealt with three more time related post processing which are ETC Step Response and Schroeder Plot The last is room acoustic oriented and we will handle it later with a T60 calculation example ETC and Step Response are shown here Fig 10 28 and 10 29 they are relative to the system of Fig 10 15 CLIO Drees DAT eee DLL dA Ft ft ft yt La Piece of furniture Floor Ly ICH Con BI NU O O S DM a Troia ULI Nik LI Interpretation of ETC aside most obvious things which are labelled inside the figure requires some theoretic digressions beyond the scope of this user manual as the topic is still debated et tT tt tt et tt S S eat tt tt A LDL Woofer Figure 10 29 Step response is very useful to identify differences in arrival time between drivers as well as their polarity 100 Chapter 10 MLS 10 6 PROCESSI NG TOOLS BY EXAMPLE CLIO has powerful processing tools that can be handful in several circumstances We saw the basics at the beginning of this chapter It was just a brief description of the kind press this to do that Here we are going to use some of them in practice Some general rules applies to group of them as the four basic operation You
82. f you identify a free PCI slot Note that it is preferable to install the CLIO board as far away as possible from the video adapter 4 Insert the CLIO board in the slot and screw it down firmly 5 Close the cabinet 6 Reconnect the mains cable but don t switch the computer on until you have connected the SC 01 Signal Conditioner This topic will be covered in 3 2 2 3 2 2 CONNECTING THE SC 01 SIGNAL CONDITIONER To connect the SC 01 Signal conditioner to your PC you need the following cables 1 1 x RS 232 DB9 Male to DB9 Female 9 pin cable RadioShack Cat 26 117 as in Fig 3 1 If the RS 232 connector available on your PC is a DB25 Male then you also need a DB25 to DB9 serial adapter RadioShack Cat 950 0271 do not use a mouse adapter as they usually don t connect all the serial contacts This cable is not supplied in the Lite version of the CLIO system Chapter 3 Installation 19 Figure 3 1 2 2 x Stereo mini jack to two RCA plugs red plus black audio cable RadioShack Cat 42 2481 These cables are not supplied in the Lite version of the CLI O system If you are going to use these cables Fig 3 2 be sure that the black RCA plug is connected to the jack s tip the inner contact Please note that some ready made cables on the market have a reversed connection E Figure 3 2 3 1 x DB15 Male to DC plug always supplied with your CLIO system Figure 3 3 20 Chapter 3 Installation To connect the SC 01 S
83. fine the highest Frequency of the Sweep This is also the starting measurement Frequency The highest value accepted is 22388 Hz The value should also be one octave higher than the Minimum Frequency Freq Min Edit Box Lets the user define the lowest Frequency of the Sweep This is also the end measurement Frequency The lowest value accepted is 10 Hz The value should also be one octave lower than the Maximum Frequency Gating Acquisition Settings Gated Check Box Lets user enable the gating acquisition mode Checking it will automatically disable the Stepped Check Box and check it That is Gated Measurements are always carried in Stepped Mode Delay Edit Box Lets user define the delay in ms applied between the signal generation and its acquisition When different than 0 it is active even when gating is not checked if Chapter 11 Sinusoidal 107 Stepped is also not checked Typical use when gated is checked is quasi anechoic Frequency Response Analysis where it removes the sound time of fly between Speaker and Microphone Alternative use with gated not checked might be removing the delay between the play and recording head in a three heads tape recorder as well as any digital processor that introduce delay in the signal path When the settings are Not Stepped and Not Gated the delay value is reset automatically to 0 CLIO introduces a large delay anyway between start of generation and acquisition The highest Delay value accepted
84. g F4 the Multi meter has also the capability of controlling the generator and of capturing the global reference level thus it can be considered the heart and control center of CLIO it is rare that you enter CLIOwin and don t use the Multi meter the information and controls available here are of invaluable importance during the normal operation of the whole instrument 8 2 MULTI METER CONTROL PANEL ER Multi Meter of x os ia s AA SIN 25 MLS WHITE PINK FILE EE CHA Fast sl 7 Ze A BER SET 0 dB 1dB AdB 0A0dB Pressure 127 17 opp THO 0033 o 0 15 voltage Off ima n Vrms Frequency 1000 Hz IMD 30 903 Filename RUNNING Figure 8 1 Multi meter control panel Chapter 8 Multi Meter 69 8 2 1 TOOLBAR BUTTONS ty Starts the measurement e Permits execution with the control panel in a minimized state Only a small stay on the top display remains visible See 8 3 2 Stops the measurement CO If pressed displays all measured parameters Captures the actual reading of the multi meter as the global reference level or microphone sensitivity refer to 8 3 3 and 8 5 1 for details A w Control the scale of the meter bar graph ci Enables disables the generator control toolbar see 8 3 1 this setting is saved within CLI Owin global settings 8 2 2 TOOLBAR DROP DOWN LISTS parameter Selects the parameter to be measured unit Selects the measurement unit channel Selects
85. ghtly around the initial value until the best fit between the calculated and measured impedance curve Is found in a large frequency range around resonance This procedure works fine and gives accuracy advantage if the driver impedance fit the Thiele and Small model pretty well Unfortunately this is not always the case Should the user encounter such cases if the parameters obtained with and without MSE differ substantially he she must be warned that the entire concept of TS parameters has loosen its usefulness This often happens with tweeters woofer whose impedance has been measured at high level defective devices 142 Chapter 13 Measuring impedance and T amp S parameters BI BLI OGRAPHY 1 Joseph D Appolito Testing Loudspeakers Audio Amateur Press 1998 2 J M Berman and L R Fincham The Application of Digital Techniques to the Measurement of Loudspeakers J Audio Eng Soc Vol 25 1977 June 3 LR Fincham Refinements in the Impulse Testing of Loudspeakers J Audio Eng Soc Vol 33 1985 March 4 S P Lipshitz T C Scott and J Vanderkooy Increasing the Audio Measurement Capability of FFT Analyzers by Microcomputer Postprocessing J Audio Eng Soc Vol 33 1985 September 5 D D Rife and J Vanderkooy Transfer Function Measurement with Maximum Length Sequences J Audio Eng Soc Vol 37 1989 J une 6 A Duncan The Analytic Impulse J Audio Eng Soc Vol 36
86. hird dimension usually time to classical amplitude frequency graphs CLIOwin permits the following 3 D types of waterfall Cumulative spectral decay CSD Energy Time Frequency ETF File display used for polar representation 12 2 WATERFALL CONTROL PANEL Ei Waterfall E x aeleze Filename Cumulative Spectral Decay Zi Figure 12 1 12 2 1 TOOLBAR BUTTONS tq Starts a waterfall calculation dh Enters the Waterfall settings dialog See 12 2 1 Expands the waterfall display changing its Y scale Three ranges are available 20 40 and 800B k Compresses the waterfall display changing its Y scale Three ranges are available 20 40 and 800B amp Enters the Marker mode see Fig 12 5 In this operating mode it is possible to inspect the single data points of each waterfall slice clicking and dragging the mouse aa When in marker mode moves the selected waterfall slice backwards The same action is obtained with the Up Arrow keyboard shortcut w When in marker mode moves the selected waterfall slice frontwards The same action is obtained with the Down Arrow keyboard shortcut Chapter 12 Waterfall 117 12 3 WATERFALL BASI CS Waterfall Settings X Waterfall Settings X General File Display General File Display Root Bile Wane Root File Name Mods cso Mode E Z Start Z Start Number Of Spectra 30 Nonmber Wh Spectra 30 E 2 Stop Z Sto Time
87. ier output must be taken with dBV as y scale and used as reference file A value of impedance is also necessary that allows Clio to convert voltage to power We will go trough the entire procedure using the tweeter of previous examples As what we are looking for is the response in 1W 1m condition we have to move the microphone to 1m from the tweeter it was at 69 14cm The 1m condition can be set directly with a meter Fig 10 32 shows the 1m measure in black and the previous one in red Level at speaker terminal is unchanged The average difference 3 90B CLIO 108 0 10 0 108 0 180 0 20 0 180 0 20 100 1k Hz 10k 20k 20 100 1k Hz 10k 20k Figure 10 32 and 10 33 We now connect Clio input to the speaker terminals change the y scale to dBV do not change Clio output level and obtain Fig 10 33 This is a nearly flat line that indicates us the voltage delivered to the speaker Remember to save the measurement to disk It is worth to point out that deviation from linearity in this curve due to the power amp or cable would be compensated by this procedure Now we reload the response at 1m go to the Process Dialog that will appear as in Fig 10 34 ele SZ twee AB AL File Impedance fe FileName ampout mls Browse Ok Cancel Figure
88. ignal Conditioner do the following ai kb wg Connect one audio cable from the card Line Out plug to the two RCA plugs on the rear panel of SC 01 labeled FROM PC red plug channel B black plug channel A 2 Connect one audio cable from the card Line In plug to the two RCA plugs on the rear panel of SC 01 labeled TO PC red plug channel B black plug channel A LA Connect the DC supply cable from the DB15 connector on the card to the dc plug on the rear of SC 01 4 Connect the RS 232 cable from SC 01 to a free RS 232 port in your computer Fig 3 4 shows the audio and dc connections as they should be used Figure 3 4 Your CLIO system hardware installation and connection is now finished The connections between the PB4281 SC 01 and your PC shouldn t normally be changed in every day work you will always use the SC 01 front panel connectors Fig 3 5 CLIO Ay Ka AUDIOMATICA O O O A A B Se A Figure 3 5 S Chapter 3 Installation 21 3 3 HARDWARE REGISTRATION WITH WINDOWS The hardware registration procedure is started automatically the first time you switch your computer on after you have physically installed the CLIO PB4281 PCI card If you are installing under Windows 95 98 or Millennium goto section 3 3 1 Windows 2000 goto section 3 3 2 Windows XP goto section 3 3 3 3 3 1 HARDWARE REGISTRATION UNDER WINDOWS 9x The procedures described refer specifically an
89. imply not able to give the correct answer We need another piece of information which is PHASE Fig 10 19 is the same measure of Fig 10 8 with phase curve overlaid To obtain it we just stored the magnitude curve and clicked on the phase button 150 0 CLIO 180 0 Ohm Deg 120 0 108 0 30 0 108 0 0 0 180 0 20 100 1k Hz 10k 20k Figure 10 19 To acoustic devices the same principles applies Fig 10 20 shows the magnitude response of woofer and tweeter in a box without cross over network 110 0 TLIO 180 0 1 00 V dBSPL Deg 0 80 100 0 108 0 0 60 Figure 10 20 and 10 21 The two measurements were taken from the same microphone position Should we ask ourselves which is the summed output we could not answer from the magnitude data alone Unfortunately acoustic phase is not so easy to handle as electric phase We are going to base our example on the tweeter whose impulse response and window settings are in Fig 10 21 Procedure for woofer would be exactly the same 96 Chapter 10 MLS We will take this opportunity to introduce the use of the Wrapped Check Box Figures 10 22 and 10 23 shows the tweeter phase curve unwrapped and wrapped 110 0 CLIO 0 0 110 0 CLIO dBSPL TT Deg dBSPL 100 0 180 0 Deg 3312 0 100 0
90. in CLIOwin Shortcuts i e keystrokes that you can press to obtain a certain action will save you time and increase your productivity Refer also to Chapter 7 to learn the measurement interface and associated shortcuts Note that the measurement specific MLS submenu FFT submenu menu are active only when the measurement control panel is open and selected 5 6 1 FILE MENU Please refer to Chapter 6 for a detailed explanation of the File Menu CLIO ELECTRICAL amp ACOUSTICAL TESTS File Analysis Controls Window Help gt Open F3 a x Ts Hr H Save F2 Autosave Alt F2 ti Notes Data Shift F2 Graphics Ctil F2 amp Print AlteP I Autoscale F6 Calibration Setup Exit Fig 5 10 File Menu F3Saves a measurement file relative to the active control panel F2Loads a measurement file relative to the active control panel ALT F2 Enters the Autosave Settings dialog box see 6 3 1 SHI FT F2 Exports the active measurement as an ASCII file CTRL F2 Exports the active measurement as a Windows Enhanced Metafile ALT P Prints the active measurement F6 Enables disables the AutoScale function see 5 4 6 Chapter 5 CLI Owin basics 47 5 6 2 ANALYSI SMENU The Analysis menu gives you a powerful way to access measurement menu and menu functions through the keyboard Here we present you all the available menu and shortcuts refer to the chapters specific to each measurement for details about it
91. ing the software for CLIO PB4281 PCI Audio WDM A Click Finish to close the wizard Back Cancel Figure 3 21 Let s now verify that the hardware installation and registration is OK Click with the right mouse button on the My Computer icon on the Windows desktop Then click Properties select the Hardware tab and press the Device Manager button as In Fig 3 22 Device Manager File Action wiew Help PROGRAMMAZIONEZ d Computer See Disk drives 3 Display adapters 2 DVD CD ROM drives H Floppy disk controllers H Floppy disk drives IDE ATA ATAPI controllers Keyboards T Mice and other pointing devices Monitors B Network adapters F Ports COM amp LPT Se Processors Ei Sound video and game controllers EN Audio Codecs e KA CMIS738 C3DX PCI Audio Device P Legacy Audio Drivers Legacy Video Capture Devices Media Control Devices Standard Game Port video Codecs System devices Universal Serial Bus controllers KREE E il Figure 3 22 The presence of the CLIO PB4281 PCI Audio WDM under Sound video and game controllers in place of the previously installed Crystal driver confirms the correct installation 28 Chapter 3 Installation 3 3 4 IMPORTANT ADVI CE If your computer has another sound card fitted in addition to the CLIO Card e
92. is in Fig 10 31 20 180 0 0 CLIO 80 0 10 0 108 0 20 0 108 0 30 0 180 0 0 100 1k Hz 10k 20k Figure 10 31 Note that the y scale has been automatically changed to dBRel This is a good point to introduce the use of Load and Save process together with the Automatic Processing Chapter 10 MLS 101 button Any process you execute can be saved to disk and will have mpro extension This allows to recall any value or file path later on by loading this file again Suppose you have a little production often speakers you want to test against a previous produced reference you know is fine You just have to define and save a process that divide current data with the reference Testing a device against itself should produce a flat line within the frequency range of the device and this should be checked before saving the process When you need to check your little batch you just recall your process This will activate the Automatic Process button When this button is down any subsequent measurement is processed before it is displayed The next process we will consider is the dBSPL Watt It requires a file and an impedance value and allows to obtain a frequency response plot referred to 1W at the speaker terminal whatever is the real measurement level To make this possible an electrical measurement at the speaker terminal power amplif
93. is 320ms Auto Delay Check Box amp Auto Delay Frequency Edit Box If Auto delay is checked when delay is handled see above CLIO tries using the Frequency settled in the Edit Box to determine the delay automatically The value found is displayed in the Delay Edit Box reopening the Settings Dialog after the measurements has been taken allows to visualise it Impedance Settings A two position Radio Button allows to choose between Internal Mode and QC Box Sense Mode The latter requires the QC Box Unit Model 2 or Model 3 See Chapter 13 Measuring impedance and T amp S parameters for details about connections and more Distortion Settings An Edit Box allows to type in the value in dB used by the graphical routines to rise the display of the distortions curves Only the display of the curve is affected The marker readings continue to display the real value which if the rise value is different than 0 differs from the curve position 108 Chapter 11 Sinusoidal 11 2 4 SINUSOIDAL POST PROCESSI NG TOOLS The POST PROCESSING Dialog gives access to very powerful tools that once defined can be saved reloaded and automatically be applied to every executed measurement Sinusoidal Processing Tools x eM e xt 20m Du Value File Real jo Imag jo Cancel tm Loads a Sinusoidal process Ee Saves a Sinusoidal process Adds a data value or compatible file to the current measurement Subtracts a data value or
94. is shown in Fig 13 12 As expected the output of the amplifier appears as a straight line Should not be so this would not be a problem as the whole procedure compensate for any deviation in the frequency response More interesting is the absolute level As Rs value is small this level appears nearly unchanged to the speaker We read 12dBV that translate in 250mV 0 0 180 CLIO 80 0 dBV Deg 10 0 108 0 40 0 108 0 50 0 180 0 10 100 1k Hz 10k 20k Chapter 13 Measuring impedance and T amp S parameters 133 Figure 13 12 Lets proceed now with the device measurement Connections need to be changed as in Fig 13 13 Weare going to measure now the voltage across Rs which is proportional to the current in the device Leaving anything in the Sinusoidal menu as it was for the previous measurement we obtain Fig 13 14 It seams a strange shape if you are not used to But in fact we are measuring Current here and Voltage being constant it decreases at resonance INPUT A INPUT B C LIO OUTPUT A OUTPUT B POWER AM EE Figure 13 11 CLIO 108 0 60 0 10 100 1k Hz 10k Figure 13 14 What we do from now on is just post processing Leaving the last measure in memory open the Processing Tools Dialog from within Sinusoidal MLS
95. kind Users however should always take the maximum effort to avoid these situations anyway Furthermore MLS has several advantage over Sinusoidal The most evident is execution time which is one order of magnitude better even using big sizes which by the way is always advisable It can measure down to 1Hz while Sinusoidal stops at 10Hz Its high sensitivity to even week non linearity can be used to reveal even small rub amp buzz problems directly from the impedance measure We advise to use Sinusoidal for the first experiences After everybody will be able to get an opinion on personal basis Chapter 13 Measuring impedance and T amp S parameters 137 13 7 THIELE amp SMALL PARAMETERS 13 7 1 INTRODUCTION CLIO handles Thiele and Small Parameters hereafter TS as a post process of impedance measurements Three options are available for data source selected by the Data Origin Drop Down Control Sinusoidal Impedance Data MIs Impedance Data File Data the last created with either of the previous There are no conceptual differences between File and the first two options aside where the data resides Choosing Sinusoidal or Mls user should have one of these measurements in memory while the File Data option will prompt for file selection Impedance measurements are therefore central topic and the previous paragraphs are an essential background To get the full set of TS two impedance curves are needed The first is the loudspeaker free air imp
96. log box Equivalent to ae CLIO ELECTRICAL amp ACOUSTICAL TESTS LV Sinusoidal Fig 5 15 Sinusoidal Submenu G Starts a Sinusoidal measurement Equivalent to Ti ESC Immediately stops a Sinusoidal measurement S Enters the Settings dialog box Equivalent to dk P Displays Phase Equivalent to d 2 Displays second harmonic Equivalent to 3 Displays third harmonic Equivalent to Ill 4 Displays fourth harmonic Equivalent to IN 5 Displays fifth harmonic Equivalent to NM Sa CLIO ELECTRICAL amp ACOUSTICAL TESTS Ee Multi Meter Fig 5 16 Multi meter Submenu G Starts a Multi Meter measurement Equivalent to k nt T Stops the Multi Meter measurement Equivalent to 50 Chapter 5 CLIOwin basics Ei CLIO ELECTRICAL amp ACOUSTICAL TES File Analysis Controle Hindow Help c III MS Dia Ay Sale S Waterfall Chien lu EFT Ctrl F a Sinusoidal Ctrl S g Multi Meter F4 Tal T amp 5 Parameters Go G d Quality Control ir Fig 5 17 T amp S Parameters Submenu G Starts a T amp S Parameters calculation Equivalent to T a 5 6 3 CONTROLS MENU The Controls Menu is the heart of your CLIO hardware learn in detail how to access hardware control through the keyboard Refer also to 5 4 2 5 4 3 5 4 4 and 5 5 File Analysis Controls Window Help a i SCH K ill Generator Esc di Generate Output Level 0 1dB Shkift FS Output Level 1 dB FO Output Level 1dB Fy Output Level
97. ls over some external hardware connected to the computer parallel port It is possible to choose the parallel port to use and then enter the available control panels The following figure illustrates the parallel port bits and how they are used by CLIO CLIOQC AMPLIFIER AND SWITCHBOX CONTROL OUTLINE ET1 ST1 CONTROL Fig 5 6 Parallel port control signals 5 5 1 CONTROLLI NG THE CLI OQC AMPLI FI ER amp SWITCHBOX ena eis CLIQGC Amplifier amp Switch Box Controls Input 1 Input 5 Input 2 Input E C Input 3 C Input Input 4 C Input 8 Imp Internal iC Impl Sense Type Sense H Ohm Model 3 0110 Fig 5 7 CLIOQC Amplifier amp Switchbox control panel This control panel helps you when you are operating the CLIOQC Amplifier amp SwitchBox You may choose the Amplifier amp SwitchBox model and set the value of the internal sensing resistor to obtain maximum precision during impedance measurements for this please refer to chapter 13 These controls are self explaining they are also treated in the unit s user s manual and in this manual everywhere else the amplifier and switchbox is used Chapter 5 CLI Owin basics 45 5 5 2 CONTROLLI NG A TURNTABLE ale ler Ss Turntable Controls L_ Single Pulse 2 Link To Measurement Resolution Deg Speed RP 5 0 0 750 Fig 5 8 Turntable control panel This control panel helps you when you are operating a turnta
98. m PNK FILE SET og 1dB ep 219 SET 0 1dB 1d8 1dB Did 25IN MLS VWHITE PINK FILE SET 01dB Ob 208 0 1dl 51 0 dBSPL 69 39 dBSPL Filename RUNNING 4 Filename RUNNING As Figure 10 12 and 10 13 Now set CLIO output level to a very low value 30 to 40dB Start the MLS signal and increase CLIO output level until you read 85 to 90 dBSPL as in Fig 10 13 This holds if you placed the microphone 70cm to 1m distant from the speaker Now go back to the Chapter 10 MLS 93 MLS Menu select dBSPL as Y scale unit and finally click on Go The speaker we are testing is a glorious Rogers LS3 5A year 1978 Fig 10 14 shows our result 180 0 Deg 108 0 108 0 Figure 10 14 What you see is the speaker plus the room where we take our measurement which is far from being anechoic It is time to inspect the time domain Clicking on the Time Domain button we get Fig 10 15 and Fig 10 16 once we zoomed to the first 11ms and expanded the y scale 0 50 Figure 10 15 and 10 16 We did also another very important thing At 7 3ms is visible the first reflection due to the floor and expected from Fig 10 11 We set the marker at 6 8ms which is just before the first reflection and set the Stop Window there see Chapter 8 5 CLIO will set to O all the values of the Impulse response af
99. ments You can call fax or write to us at AUDIOMATICA SRL VIA MANFREDI 12 50136 FLORENCE ITALY PHONE 39 055 6599036 FAX 39 055 6503772 AUDI OMATI CA ON LINE For any inquiry and to know the latest news about CLIO and other Audiomatica s products we are on the Internet to help you AUDIOMATICA website www audiomatica com CLIOwin website www cliowin com E MAIL info audiomatica com Chapter 1 Introduction 9 AUDI OMATI CA S WARRANTY Audiomatica warrants the CLI O system against physical defects for a period of one year following the original retail purchase of this product In the first instance please contact your local dealer in case of service needs You can also contact us directly as outlined above or refer to other qualified personnel WARNINGS AND LIMITATIONS OF LIABILITY Audiomatica will not assume liability for damage or injury due to user servicing or misuse of our product Audiomatica will not extend warranty coverage for damage of the CLIO system caused by misuse or physical damage Audiomatica will not assume liability for the recovery of lost programs or data The user must assume responsibility for the quality performance and the fitness of Audiomatica software and hardware for use in professional production activities The CLIO SYSTEM CLI Owin and AUDIOMATICA are registered trademarks of Audiomatica SRL 10 Chapter 1 Introduction REGISTRATION CARD AUDIOMATI CA REGISTRATION CARD EMAIL OR F
100. more information on this topic In both conditions the loudspeaker is driven from a high impedance source and its damping is only mechanical Fig 11 1 shows a 6 woofer driven by a 1000hm output impedance generator delivering a sinusoidal burst 200ms long at its resonance frequency When the excitation stops the device continues to move and therefore produce back electromotive force voltage for more than 50 ms Something very similar happens at start up In this situation tf CLIO is set in not stepped mode it will acquire the previously played frequency together with the actual 0 200 V 0 120 0 040 0 040 0 120 0 200 0 00 50 100 150 200 250 300 350 400 ms 450 500 Figure 11 1 Fig 11 2 shows the same driver impedance taken both in stepped black and not stepped mode red The not stepped curve is simply wrong Conclusion use always stepped mode if the behaviour of the device to be measured is unknown 180 0 Deg 108 0 108 0 10 100 1k Hz 10k 20k Figure 11 2 110 Chapter 11 Sinusoidal 11 3 2 FREQUENCY RESOLUTION Here the lowest resolution the fastest is the measuring time Impedance measure ments are again a p
101. mp SWITCHBOX SENSE FROM CLIO INPUT 1 INPUT 2 GAIN 10dB Model 1 2 amp 3 INPUT N o GAIN 20dB Model 4 Figure13 10 Before proceeding whatever in MLS or Sinusoidal remember to go in the Settings Dialog and select Sense under Impedance CLIO s output level has to be set to a much lower level than in Internal Mode We have seen before that with 10dBu out we had 0 316V at speaker terminals at resonance Should you let this level you would have 7 75V at any Frequency 20 to 30 dBu are reasonable output level to start with The CLIOQC Amplifier gain is 10dB Model 2 amp 3 or 20dB Model 4 ittherefore multiply CLI O s output by 3 16 Model 2 amp 3 or 10 Model 4 As the output impedance is close to 0 no further attenuation occurs once the speaker is connected Finally we deal with measuring accuracy in this case The sensing resistor value has been stated as around 0 1 Ohm It is very difficult to keep such a low value within a reasonable tolerance and therefore the real value is going to change between units The default value that comes is 0 127 Ohm User can further adjust this value using a reference resistor of Known value in the 10 Ohm range the real value can be eventually measured with high accuracy using internal mode Simply take an impedance measurement of the known resistor and adjust the Sense value displayed multiplying it by the ratio between the know resistor 132 Chapter 13 Measuring impedance and T amp S paramet
102. n Entering our data directory we find the situation in Fig 12 14 124 Chapter 12 Waterfall Choose one file within a set e rcf deg 2000 A ref deg 2500 S deg 2500 SE cf deg 3000 rcf deg 3000 ni rcf deg 3500 E ref deg 4000 E ref deg 4000 rcf deg 4500 rcf deg 4500 rcf deg 500 E ict deg 501 Rj ref deg 5C rcf deg 551 ref deg 5E rcf deg 60I rcf deg 3500 rcf deg 1000 Figure 12 14 The set of files is composed by 25 files it is sufficient to choose one of them It is now important to give the initial and last files for display this is done with the Z start and Z stop values to be input as in Fig 12 15 We chose to display only responses from 40 to 40 Waterfall Settings Owen Wh Spectra Time Shite iis SA i i Ire HEIEIENGE Figure 12 15 We are at last ready for the waterfall The result is in Fig 12 16 Eli Waterfall Figure 12 16 Treating polar data we may be more interested in referencing the graph to the response that our speaker shows on axis This is easily done inputting the relative value in the Z ref box inside the waterfall settings Fig 12 17 Chapter 12 Waterfall 125 Waterfall Settings NOTE Wh Specie Ime Siaith is CRA pi line Ir Refere AAA e Figure 12 17 The final result for our polar data waterfall is in Fig 12 18 the response at 0 degrees is now flat and our plot identifies perfectly the behavior of the speaker put
103. nced user to understand what is going on just by inspecting the results Checking the measuring level is important especially when the gain of the device under test is unknown You should use the Multi Meter and the MLS Signal to accomplish this 10 4 2 MLS SIZE The Mis Size is the number of points that defines the MLS sequence In terms of generating a digital signal these are the numbers of samples before the signals is started again from the beginning CLIO handles MLS sizes from 4k to 128k These terms are inherited by the computer world and are somehow imprecise The real size is the nearest power of 2 the 4k being 4096 points and the 128k 131072 points long one less The first important consequence of setting the Mls size is the length of the Impulse Response recovered which is always as long as the Mls itself From the user point of view what matters is how long this impulse is in terms of seconds This in turns depends also on the Sampling Frequency set It is easily calculated as the size divided by the sampling frequency The default is 16k and 51200Hz that is 16384 51200 0 32 seconds We will 90 Chapter 10 MLS deal with this in more detail later Here is enough to say that CLIO uses this size also for the FFT This is important as the frequency resolution you get is calculated as the Sampling frequency divided by the FFT size Again for the default settings this is 51200 16384 3 125Hz This is already a high resolution However
104. ng with numerical data on floppy disk is released by Audiomatica and specifies the frequency behaviour of the single microphone under test The file data can be used with the CLI Owin software see 5 4 5 2 2 4 THE MI C 01 OR MI C 02 LITE MICROPHONE In the Lite version of MIC 01 and MIC 02 the accessories wooden case 2 7 m cable and stand adaptor are not supplied 16 Chapter 2 The CLIO System 2 3 THE PRE O1 MI CROPHONE PREAMPLIFIER The microphone preamplifier PRE 01 has been designed to match Audiomatica s microphones MI C 01 and MI C 02 It is particularly useful when the microphone has to be operated far from the analyzer or when weighted measurements are needed PRE 01 powers the microphone connected to its input with an 8 2V phantom supply and adds a selectable weighting filter A or B or C also available there is a 20 dB gain stage The unit is operated with two standard 9V batteries or with an external DC power supply PRE 01 substitutes the 3381 A preamplifier 2 3 1 TECHNICAL SPECI FICATION Frequency response 7Hz 110kHz 3dB Weighting filter A B C IEC 651 TYPE I Phantom power supply 8 2V 5600 Ohm Gain O amp 20dB INTERNAL SETTINGS Input impedance 5600 Ohm Output impedance 100 Ohm Maximum output voltage 1kHz 25 Vpp THD 1kHz 0 01 Input noise 20dB gain 7uV LIN 5 3uVA Drive capability 7mA Batteries duration gt 24h alkaline cells Size 12 5 w x19 d x5 h cm Weight 900g
105. nsure that this card and NOT the CLI O Card is chosen as the preferred card This will ensure that all system sounds will be played by the other device Open the audio properties under the Control Panel and select the second card as the preferred The example in Fig 3 23 refers to a C Media audio device under Windows 2000 Professional refer also to Fig 3 15 for a device map of the same PC Sounds and Multimedia Properties KE Sounds Audio Hardware m Sound Playback si _ Preferred device J AEE C Media PCI Volume Advanced Sound Recording Va Preferred device p A C Media PCI pis Volume Advanced MIDI Music Playback oyn d an d Pia Preferred device Multimedia as Microsoft GS Wavetable SW Synth v Volume About I Use only preferred devices Cancel Apply Figure 3 23 Chapter 3 Installation 29 3 4 SOFTWARE INSTALLATION This paragraph deals with software installation The CLIOwin software is provided either on its own CD ROM or in electronic format as a single self extracting executable file Figure 3 24 ZS Es setup 41547124 Inthe first case the CD ROM root will contain a file named setup exe while in the second the file will be named with your system s serial number 41947124 exe as in Fig 3 24 click on these files to start the software installation Fig 3 25 If you are installing under Windows 2000 or XP please be sure to have admini
106. o display phase data wrapped at 180 degrees boundaries or unwrapped impedance When taking impedance measurement refers either to the internal impedance mode or to the I Sense feature of the CLIOQC Amplifier amp SwitchBox Model 2 and 3 Chapter 10 MLS 87 10 2 4 MLS POST PROCESSING TOOLS GR Fe xt twee ZAOn D Value File Real o Imag fo Cancel Figure 10 3 Gm Loads an MLS process al Saves an MLS process Adds a data value or compatible file to the current measurement Subtracts a data value or compatible file to the current measurement AS Multiplies the current measurement by a data value or compatible file Divides the current measurement by a data value or compatible file ER Shifts the current measurement by a dB value xj amp Multiplies the current measurement by complex frequency sJ Divides the current measurement by complex frequency Fi Uses a reference measurement file taken at speaker terminals to calculate 1m sensitivity in dBSPL W The reference file should have dBV Y units while the one in memory should be in dBSPL Process the current measurement with an octave band filter It is possible to input the midband value and the filter bandwidth 3 Temporally shifts the current measurement by a ms value Affects phase response Merges the current measurement with the part below the selected transition frequency of a selected compatible file Cc Combines the actual measurement an
107. of driver including air load Volume of air having the same acoustic compliance as driver suspension DC electrical resistance of voice coll Q of driver at F considering mechanical losses only Q of driver at F considering electrical resistance only Q of driver at F considering all driver losses Motor strength product of B times Acoustic pressure produced by the driver at 1m when driven by 2 83 V Effective surface area of the driver cone Mechanical compliance of driver suspension Mechanical mass of driver cone assembly including air load Mechanical resistance of driver suspension losses Acoustic compliance of driver suspension Acoustic mass of driver cone assembly including reactive air load Acoustic resistance of driver suspension losses Electrical capacitance representing the driver total moving mass Electrical inductance representing the driver mechanical compliance Electrical resistance representing the driver mechanical losses Total acoustic resistance of driver Total mechanical resistance of driver Suspension losses electrical reflected Mechanical mass of driver cone assembly excluding air load Minimum impedance in the frequency range above F Impedance at F Average of impedance modulus over the measured frequency limits Efficiency Chapter 13 Measuring impedance and T amp S parameters 139 L Inductance at 10kHz 1kHz L Inductance at 10kHz 10kHz 13 7 3 TS STEP BY STEP Getting TS re
108. of the impulse you have to subtract In practice we do not encourage distance below 70cm for complete speaker measurement and you should increase to 1m for bigger ones However single driver measurement can take advantage from a reduced distance Chapter 10 MLS 95 10 4 4 PHASE amp GROUP DELAY We used the term Frequency Response to refer to graphics the kind of Fig 10 5 and Fig 10 8 Frequency is in the x axis in both figures The units that respond to frequency y axis are Volt and Ohm respectively Both of them are complex quantities have real and imaginary part and their magnitude is shown Doing this we obtained a very useful piece of information but we lost the original data infinite numbers of different real and imaginary part can lead to the same magnitude How this information loss will affect your life depends on what you are going to do with these graphs or better which was the original question you were trying to answer Referring to Fig 10 5 A reasonable question could have been how much does A filter attenuate signal at 100Hz in respect to 1kHz You go trough the graph with the marker and answer 19 3dB If you have the IEC 651 norm you can go to the A filter specs and you will find this attenuation should be 19 1dB 0 5dB for type 0 devices End of your job Lets now pose another question referring to Fig 10 8 how much a 10kHz tone would be attenuated if we wire a 10 ohm resistor in series with that woofer We are s
109. ol panel It is important to note that the following menu save more than one data file type MLS saves frequency response files mls and impedance response files mlsi Sinusoidal saves frequency response files sin and impedance response files SINI The extension is automatically chosen by CLIOwin 58 Chapter 6 System Operations and Settings Invokes the Autosave Settings dialog Itis possible to define the autosaving rules that will be followed by the measurements capable of this feature MLS and Sinusoldal AutoSave Settings an Te fps N Fath CAclio2000 D ata Root File Name ret deg Start 45 Increment E Total Number i J Fig 6 3 Autosave settings There are four settings which serve to define the autosave file name Path defines the folder where the file will be saved it is possible to choose it clicking on the browse for folder button In Fig 6 3 we see path defined as c clio2000 data Root File Name defines the part of the file name that will not change during autosave in Fig 6 3 it is rcf deg Start defines the initial number appended to the root This number will always be multiplied by 100 to give space for two decimals management Numbers are appended with spaces In Fig 6 3 start is 45 this will define the first autosaved file name as ci clio2000 data rcf deg 4500 Increment defines the increment to be given to the autosaved file names In the example of Fig 6 3 the second
110. ontrol external RS 232 devices St EI gi pe SUITE Fig 6 9 Chapter 6 System Operations and Settings 63 6 3 7 STARTUP OPTIONS AND GLOBAL SETTI NGS You can start CLI Owin directly clicking on the cllowin exe executable that is saved In the installation directory usually C Program Files Audiomatica Cliowin you may access CLIOwin either from Start Menu gt Programs gt Cliowin or creating a shortcut on your Desktop A second way to run CLI Owin is to click on a registered file in this way you will not only run the program but also load the file into the appropriate measurement menu CLI Owin relies during startup on a configuration file named cliopci stp which resides in the installation directory This file is written each time the program ends and saves several settings that will be reloaded and reconfigure your system Among them we find generator output level see 5 4 2 input sensitivity see 5 4 3 phantom power supply state see 5 4 3 autorange state see 5 4 3 microphone settings see 5 4 4 and 7 4 1 CLIOQC Amplifier amp SwitchBox settings see 5 4 5 color scheme and other setup settings see 6 3 6 main window state multi meter generator control state see 7 2 1 global reference level see 7 3 3 autoscale state see 5 4 6 Note It is possible to return the system to its initial default state after installation deleting the cliopci stp file 6 3 8 SAVING MEASUREME
111. ossible to choose a size between 256 and 65536 points Sampling Selects the sampling frequency Hold Function Selects either Min or Max hold function This functionality is activated by the relative toolbar button Freq Axis Selects among four possible FFT or RTA operating modes Linear frequency axis narrowband Logarithmic frequency axis narrowband 1 3 Octave filtered RTA 1 6 Octave filtered RTA Delay Permits the input of the desired processing delay in ms when in Internal Trigger mode See 9 7 for details Averaging Selects either linear or logarithmic averaging see Averaging 9 6 for details Chapter 9 FFT 79 9 4 FFT AND RTA OPERATI ON The FFT and RTA measurements and also Multi meter ones see Chapter 8 differ from MLS and Sinusoidal ones in the fact that they are interactive the user has control over measurement time and generated stimuli You may obtain from them only answers about unknown signals without any care for generating a stimulus or you may leave to others this job like when you measure an audio chain relying on the test signals contained in a CD ROM One effect of this is that strictly speaking FFT measurements may lead to less precise results if compared to other techniques the possibility of injecting a synchronous MLS sequence at the beginning of the same audio chain mentioned before is surely a better approach even if in the vast majority of cases unfeasible FFT and RTA powe
112. ou will be prompted by the Export dialog Depending on the measurement menu you are working with it will be possible to choose different data for export Here Is a list of the possibilities menu by menu MLS gt Display Frequency Data The program will export the frequency data as they are displayed on the screen with resolution variable from 256 to 2048 points regardless the current MLS size MLS gt FFT Frequency Data 60 Chapter 6 System Operations and Settings The program will export the frequency data with the resolution of the current MLS size MLS gt Time Data The program will export the acquired impulse response or active post process FFT gt Display Frequency Data The program will export the processed frequency data as they are displayed on the screen with its internal resolution of 2048 points regardless the current FFT size FFT gt FFT Frequency Data The program will export the processed frequency data with the resolution of the current FFT size FFT gt Last FFT Data The program will export the last calculated FFT frequency data with the resolution of the current FFT size FFT gt Last Time Data The program will export the last captured time data with the resolution of the current FFT size Sinusoidal gt Frequency Data The program will export the acquired frequency data with their fraction of octave frequency resolution Sinusoidal gt Frequency Data Harmonics As above plus harmonics data T
113. oubleshooting section Chapter 4 3 6 1 INITI AL TEST Let s now execute our first test measurement play and capture a 1kHz sinusoid First of all click on the In Out a Loop button for channel A in this way the CLIO Box connects output A with input A with an internal relay This connection is very important as lets you capture and analyze a signal generated by CLIO without the need for an external connecting cable Then click on the generator di icon to play the 1kHz sinusoid 1031 25Hz to be exact 32 Chapter 3 Installation more on this later it s the default signal Then press the F4 keystroke to invoke the Multi Meter as In Fig 3 28 CLIO ELECTRICAL amp ACOUSTICAL TESTS Iof x File Analysis Controls Window Help SHAS MRL ve og VE a amp Oa ee o TE E Multi Meter JDL x hy S Vottage Ra zl SZ cHa Fast 7 av I BE SIN ES MLS WHITE PINK FILE SET 0108 1dB 1dB 07108 0 690 vms Figure 3 28 If everything is OK you should obtain a reading of circa 0 7V variable between a minimum of 0 6V and a maximum of 0 9V which is the mean output level of a sinusoidal signal when the system is not calibrated To conclude your intial test execute the calibration procedure described in the following section Repeating the test described after the system has been calibrated you should get the reading of 0 77V 2 2dBV which is the calibrated output level of a sinusoidal signal
114. out of user control for automatic scale adjustment and triggering of the displayed signal The time information displayed are the processed data only The user can zoom in and out these data but it is not possible to display more than one acquisition area Fig 9 8 shows this effect the same 100Hz sinusoid as before seems now truncated this means only that we reached the maximum displayable data in case of a 16K FFT 51200Hz Sampling this is exactly 320ms Wa FFT D x eG E aes lt p Rectangular sl sl si 100 1k Hz 10k 20k Filename CHA dBY 51 2kHz 16384 Rectangular E Figure 9 8 9 7 FFT AND MULTI METER There is a close interaction between FFT and Multi meter operations The two measurements share the same acquisition and processing core Should they operate together the FFT control panel acts as master while Multi meter follows as slave In this situation among other peculiarities the Go and Stop buttons of the Multi meter are disabled if an FFT acquisition is started then the Multi meter runs as well the same when you stop the measurement More on this in section 7 6 84 Chapter 9 FFT 10 MLS 10 1 INTRODUCTION MLS Analysis MLS stays for Maximum Length Sequences is a powerful well established technique that allows carrying out analysis of linear systems recovering the Impulse Response of the device It is therefore a Time based analysis Frequency domain information is obtained calculating th
115. owerful setup to exploit problems Fig 11 3 shows two impedance taken from the same 16 woofer with 1 24 octave resolution red and 1 6 octave resolution black Deriving T S Parameters from the black curve would lead to serious errors This is an extreme case a huge woofer with high Qms Different curve shapes can be accurately quantified even with 1 3 octave resolution 108 0 180 0 10 100 Hz Figure 11 3 Chapter 11 Sinusoidal 111 11 3 3 GATING Enabling Gating allows quasi anechoic Frequency Response to be carried out in normal environments with obvious and less obvious limitation Regarding the geometrical environment required Sinusoidal analysis does not differ from what has been said about MLS Nevertheless the latter give a much more intuitive approach It is strongly suggested to become very familiar with quasi anechoic measurements using MLS before dealing with gating What follows is a brief description of the parameters involved We are going to use some figures to help our intuitive grasp Fig 11 4 repeated from the MLS chapter show a typical setup while Fig 11 5 shows what really happens using as stimuli a 20ms 1kHz Sinusoidal Burst SPEAKER MIC Kei ce et I Ee e e ES E I 70 cm 2 03mS FIRST REFLECTION 250 CM 7 26mS b i 120cm l ABSORBING MATERIAL i FLOOR Figure 11 4
116. pect Go to the waterfall settings dialog and input 0 1ms Time Shift After recalculating it you obtain the plot in Fig 12 7 as you notice now the slices are closer in time decaying modes are more evident Since the time span chosen for this waterfall was about 6 1ms the maximum allowed Time Shift you could input was around 0 2ms considering 30 spectra as this was the case Figure 12 7 Chapter 12 Waterfall 121 Let s now change the CSD aspect again Go to the waterfall settings dialog and check the Reference box After recalculating you obtain the plot in Fig 12 8 as you notice now the slices are referenced to the first one the rearmost decays of different frequency regions can now be more easily compared Now change the Windows Rise Time from the default 0 58ms to 0 1ms and recalculate the CSD The result is given in figure 12 9 122 i WA BANNAN LA NURIA Figure 12 9 Chapter 12 Waterfall 12 5 MEASURI NG AND REPRESENTING LOUDSPEAKER POLAR DATA Suppose now we want to measure and give a graphical representation of the polar response of the same speaker analyzed in 12 4 We need to measure its anechoic frequency response at various angles with MLS and save the files following the rules given in 12 3 2 We will use a turntable Outline ET ST under CLIOwin s control and the automation possible within the MLS control panel 12 5 1 PREPARI NG THE MLS CONTROL PANEL For this test we would lik
117. prompt and reach the end of the wizard Found New Hardware Wizard Completing the Found New Hardware Wizard LY CLIO PB4281 PCI Audio WDM Digital Signature Not Found M x The Microsoft digital signature affirms that software has been tested with Windows and that the software has not been altered since it was tested The software you are about to install does not contain a Microsoft digital signature Therefore there is no guarantee that this software works correctly with Windows CLIO PB4281 PCI Audio WDM Windows has finished installing the software for this device The hardware you installed will not work until you restart your computer If you want to search for Microsoft digitally signed software visit the Windows Update Web site at http windowsupdate microsoft com to see if one is available Do you want to continue the installation i No More Info To close this wizard click Finish Figure 3 14 Let s now verify that the hardware installation and registration is OK Click with the right mouse button on the My Computer icon on the Windows desktop Then click Properties select the Hardware tab and press the Device Manager button as in Fig 3 15 E Device Manager Action view i pe ePROGRAMMAZIONEZ H Computer H E Disk drives ER Display adapters H A DYD CD ROM drives aS Floppy disk controllers H E Floppy disk driv
118. quires two impedance measurements As we will use both methods we need three the first relative to the driver in free air the second to the driver with a known mass delta mass added to the cone the third to the driver loaded with a known volume delta compliance Fig 13 20 shows the results of the three measurements overlaid in one single graphic 50 0 180 0 40 0 y 108 0 Tu TI TI N l 20 0 36 0 10 0 Bil DE ug fu 108 0 10 100 10k Figure 13 20 The black curve refers to free air the red to delta mass the green to delta compliance As you can see adding a Mass determines lowering Fs while loading the cone with a closed volume will increase Fs Always check this is the case to avoid errors in the post processing routine As deriving TS parameters can be performed at any successive time after the impedance measurements has been taken we suggest to save them with meaningful names as well as to use the Notes Dialog to store the measuring conditions as mass weight and or volume The last step before pressing Go in the TS dialog is to measure both the voice coil DC resistance and the effective cone diameter in millimeters In this example they are 6 41 Ohm and 133mm Finally we select File Data as data origin and pressing Go we get the following prompt Dialog T amp S Parametrs Input Ea Manufacturer Example Model D Re Ohm Cancel 140 Chapter 13 Measuring impedance and T amp S parameters After right valu
119. quisition Another important feature when averaging is the possibility of continuing averaging after a measurement is stopped has reached its target or a previous measurement has been loaded from disk CLI Owin has this capability when selecting continue in the drop down menu available aside the Go button Fig 9 5 ea gt vw Continue io OH Figure 9 5 Selecting the continue option allows as an example for spatially averaged measure ments Fig 9 6 shows two 1 3 octave RTA measurements of a small HT satellite at listening position the black one is a single 10 averages measurement taken on axis the red one is instead built using the continue option adding a total of eleven 10 averages measurements taken moving from 25 degrees left to 25 right of the speaker itself 82 Chapter 9 FFT TA e P TI Figure 9 6 Chapter 9 FFT 83 9 6 TIME DATA DISPLAY OSCILLOSCOPE The time data Fig 9 7 is an ancillary display to an FFT or RTA executed measurement Here we see a 100Hz sinusoid captured and analyzed with a 16K FFT _ BEE Tea e meses Rectangular sl sllag IN D 1 a v a YV e A S oa momagganan an aye CS KI I T ac ttt IU 1 di set III SO Lu III S DO soi TL TITTI III TITTI di 20 100 1k Hz 10k 20k Filename CHA dBY 51 2kHz 16384 Rectangular 4 Figure 9 7 The time data display has a number of particular features that allow
120. r depends not only on the measurements settings themselves but also on the generated signals CLI Owin adds the possibility of internal trigger and relative delay i e triggering with respect of the generated signal thus obtaining a synchronous capture Let s see how a measurement presented in section 11 4 was done please refer to figures 11 9 11 10 and 11 11 We have an acoustical measurement of a tweeter done stimulating it with a 2kHz 10ms tone burst see 5 4 2 for details about programming a bursted sinusoid the FFT measurement is done in internal trigger Fig 11 9 shows the analysis and the captured time data that clearly show the flight time from the tweeter to the microphone Fig 11 9 even if the analysis is not our final target show the power of synchronous acquisition which permits to display the arrival delay of sound to the microphone To obtain the desired result as explained in 11 4 it is necessary to remove the flight time plus the device settling time this can be easily accomplished setting the internal trigger delay in FFT settings to 1 5ms the final result shown is shown in 11 11 and permits the identification of the device harmonic distortion To proceed further one could vary the stimulus amplitude and test the distortion of the tweeter at different amplitudes using bursts prevents also the damage of the unit as the overall power delivered to It rather low and a direct function of the duty cycle of the burst itself O
121. r for technical support or for software upgrade When using your CLIO system you will normally use the SC 01 front connectors the connections between the SC 01 and the PB 4281 card are normally left untouched AS you ll become extremely familiar with this hardware unit we are going to give it a nickname from now on we will call it the CLIO Box Also the CLI Owin software refers to it with this nickname Chapter 3 Installation 31 3 6 RUNNING CLIOWI N FOR THE FIRST TIME If you have completed the preceding installation procedure you are ready to run CLIOwin The following steps will guide you through a complete verification of the system performance and operation From the Start Menu choose Programs then Cliowinpci and click on the CLI Owin ICON The program should start smoothly and present the main desktop Ge CLIO ELECTRICAL amp ACOUSTICAL TESTS Iof x File Analysis Controle Window Help EZE gt His Usel sie e aE ed 0E a Aly Measurement control Generator control Input control In Out loop Phantom Qutput level Input sensitivity QCBox control Internal temperature If the proper serial port has not been selected or if the serial cable is not connected you may receive the following message Cliowin The CLIO Box ts not responding To select the correct serial port go to File gt Setup gt Hardware see also 6 3 6 Should CLI Owin display an error message take note of it and go to the tr
122. rming acoustical measurements of a loudspeaker Please note this schematic diagram drawn in the assumption of using one Audiomatica microphone MI C 01 or 02 directly connected to CLIO input the output of the power amplifier is connected to the loudspeaker with an inversion in cables polarity this compensates the fact that MIC 01 and MIC 02 microphones are phase inverting as almost the vast majority of measuring microphones found in the market when making polarity measurements always cure the measuring chain in this respect considering that the CLIO hardware itself is NON INVERTING and that all calibrations are usually made under this assumption any external device like amplifiers microphones accelerometers preamplifiers etc has to be carefully checked INPUT A OR B CLIO OUTPUT A OR B MIC 01 OR MIC 02 Pee POWER AIVPLIFIER Figure 5 23 54 Chapter 5 CLI Owin basics 5 7 3 CONNECTING THE CLI 0QC AMPLI FI ER amp SWI TCHBOX Fig 5 24 and Fig 5 25 show the connections of a CLIOQC Amplifier amp Switch Box to CLIO In Fig 5 24 the unit has its internal switcher set for response measurements INPUT A INPUT B C L IO OUTPUT A OUTPUT B LPT PORT CLIOQC AMPLIFIER amp SWITCHBOX SENSE FROM CLIO INPUT 1 INPUT 2 GAIN 10dB Model 1 2 amp 3 INPUT N o GAIN 20dB Model 4 Figure 5 24 In Fig 5 25 the unit has its internal switcher set for impedance measurements using Internal Mode refer to Ch
123. s selected below Cancel Copy manufacturer s files from D Inf2k v i Ceme Ferae Files of type Setup Information inf Figure 3 19 Ignore the message This driver is not digitally signed press Next ignore the subsequent message about Windows Logo testing press Continue Anyway Fig 3 20 Hardware Update Wizard Hardware Installation Select the device driver you want to install for this hardware The software you are installing for this hardware Select the manufacturer and model of your hardware device and then click Nest If you CLIO PB4291 PCI Audio WD H have a disk that contains the driver you want to install click Have Disk has not passed Windows Logo testing to verify its compatibility Show compatible hardware with Windows AP Tell me why this testing is important Model Continuing your installation of this software may impair CLIO PB4281 PCI Audio WDM or destabilize the correct operation of your system either immediately or in the future Microsoft strongly recommends that you stop this installation now and contact the hardware vendor for software that has passed Windows Logo testing A This driver is not digitally signed Tell me why driver signing is important Figure 3 20 You should be prompted by the following success message Chapter 3 Installation 27 Hardware Update Wizard Completing the Hardware Update Wizard The wizard has finished install
124. s the active curve in it is possible to execute multiple zoom in actions A Zooms out the active curve completely i e returns to the default initial zoom state 1 Stores the active curve into overlay 1 It also displays overlay 1 2 Stores the active curve into overlay 2 It also displays overlay 2 Stores the active curve into overlay 3 It also displays overlay 3 4 Stores the active curve into overlay 4 It also displays overlay 4 5 Stores the active curve into overlay 5 It also displays overlay 5 Switches on and off the respective overlay It also shows the color of the overlay 7 4 HOW TO ZOOM 1 Click on the Zoom button 2 Position the mouse and PRESS the left mouse button at the beginning of your selection and maintain the mouse button pressed Don t just click otherwise you get a warning message 3 With the mouse button pressed move the mouse until the second selection point 4 Only now release the left mouse button Be careful you must have the button pressed from point 2 to point 4 7 5 SHORTCUTS AND MOUSE ACTIONS The following keystrokes and mouse actions are active up arrow equivalent to on the active graph Shift up arrow equivalent to on the active graph 66 Chapter 7 Common Measuring I nterface down arrow equivalent to e on the active graph Shift down arrow equivalent to k on the active graph mouse click activates the graph useful when more than one graph is present
125. strative rights The procedure is completely automatic and will only request you to accept the Software End User s License Agreement and input some information in order to correctly install CLIOWin the software installer will also check your operating system version and in certain cases will request you to restart Windows in order to finalize the installation GG CLIOWin Installation Wizard Welcome to the Installation Wizard for CLIOWin The Installation Wizard will install CLIOW in on your computer To continue click Next WARNING This program is protected by copyright law and international treaties Figure 3 25 i Cancel After successfully completing this procedure take note of the installation directory of CLI Owin usually C Program Files Audiomatica Cliowinpci 30 Chapter 3 Installation 3 5 THE CLIO BOX A few words about the SC 01 Signal Conditioner Figure 3 26 This unit is needed to correctly interface analog signals to the PB 4281 PC card it is also important as it has an internal reference used to calibrate the system and also stores the system s serial number inside its internal EEPROM Fig 3 27 shows how to find your CLIO system serial number and SC 01 firmware release after you have removed the upper cover o 37010009 Firmware release Serial number Figure 3 27 The serial number is very Important and should be mentioned each time you get in contact with Audiomatica eithe
126. t correspond then CLI Owin will operate in demo mode only 1 1 1 WHAT THIS USER MANUAL DOES COVER The CLIO System is a complete electro acoustic analyzer There are thousands of books on many of the topics that CLIO handles as a measurement system The simple definition of Frequency Response could be extended to a book itself This User Manual is intended only as a guide to allow the user to quickly become efficient in using the CLI O system its user interface its hardware features and limits Every topic is handled through real life examples with dozens of actual measurement being presented for clarity It is therefore a HOW TO manual WHY is left to the reader to explore through other literature and should be considered as essential reading There is however reference 1 Testing Loudspeakers by Joseph D Appolito which in our opinion is the perfect complement of what is covered here Anyone who feels that WHY and HOW is strongly related should seriously consider buying this wonderful book 1 2 GENERAL CONDITIONS AND WARRANTY THANKS Thank you for purchasing your CLIO system We hope that your experiences using CLIO will be both productive and satisfying CUSTOMER SUPPORT Audiomatica is committed to supporting the use of the CLIO system and to that end offers direct Support to end users Our users all around the world can contact us directly regarding technical problems bug reports or suggestions for future software enhance
127. taken as successive frequency responses saved in files In order to identify the set of files it is important that all of their names follow a particular syntax that give certain information to the processing routines The syntax follows lt NAME gt lt UNITS gt lt VALUE 100 gt MLS NAME is a common file name UNITS are the common measurement units to be displayed in the graph as Z axis label and VALUE is a unique value identifying the single file these quantities needs to be separated by spaces it is possible to give negative numbers to VALUE For example mydriver deg 250 mls is a valid file name as the name tells it is a measurement named mydriver with units deg taken at 2 5 250 divided by 100 units value It is possible to identify one file within the set as reference with the Z ref value all calculations will then be made referenced to it Please refer to 12 5 for an example Chapter 12 Waterfall 119 12 4 MAKING A CUMULATIVE SPECTRAL DECAY A cumulative spectral decay starts from an MLS measurement in memory Suppose we have an anechoic frequency response of a medium sized pro speaker 12 midbass and horn compression driver as in Fig 12 3 and 12 4 Let s first inspect its impulse response and select a reflection free part of it This data will characterize both the MLS quasi anechoic response and the waterfall postprocess selecting the start and stop window points we give the two first information to waterfall zero
128. tant as well should be very close to 0 All this must happens in the entire frequency range Notice that Fig 13 3 which refers to MLS extends low frequency limit to 1Hz while Sinusoidal Fig 13 2 stops at 10Hz which is the lowest possible If you are not getting Similar results do not proceed with a loudspeaker impedance measurement You would only add problems we will see soon to a not working procedure Even in internal mode CLIO s output level is left to the user We set it at 10 here as resistors are hopefully the most linear devices we can get As we had very comfortable results lets proceed with a Loudspeaker 50 0 180 CLIO 80 0 50 0 CLIO 180 0 Ohm Deg Ohm Deg 40 0 108 0 40 0 108 0 10 0 108 0 10 0 108 0 0 0 180 0 0 0 180 0 10 100 1k Hz 10k 20k 1 10 100 Hz 1k Figures 13 2 and 13 3 13 3 1 MEASURING IMPEDANCE OF LOUDSPEAKERS We will start with a 5 woofer using Sinusoidal our preferred choice with the following Settings Sinusoidal Settings Sweep Setting i Impedance Settings i Stepped Ge Internal Resolution 24 Octave eg l C GC Box Sense Freg Max Hz 22388 Auto Delay Distortion Settin Freq Min Hz Auto Del Freg Hz Rise dB 10 10000 30 000 cc Aside frequency range which can be changed witho
129. ter 6 8ms before FFT is executed In this way we simulate a reflection free environment Clicking on the Frequency Domain Button we obtain Fig 10 17 20 100 1k Hz 10k 20k Figure 10 17 94 Chapter 10 MLS Now things look much better and this is the almost anechoic response of the speaker Almost means that nothing comes for free The low frequency part of the response seams quite optimistic for such a little speaker The price we paid in setting to 0 the impulse tail is that we lost information on the lower part of the spectrum The transition frequency between meaningful and meaningless data Is calculated as 1 divided by the selected impulse length In our case we selected a 6 8ms long impulse 1 0 0068 147Hz right Wrong We have the first 2 ms of the impulse which is the time of sound flight that does not carry any information We could have selected the impulse as in Fig 10 18 without affecting the frequency response at all Phase response would have been greatly affected Figure 10 18 The right calculation is 1 0 0068 0 002 208 33Hz In our room the smallest dimension is floor to ceiling This is indeed the most frequent case This dimension is however 4m The best location for the speaker would have been at 2m both from the floor and the ceiling The second consideration is microphone distance The highest it is more is the useless part
130. the input channel integration Selects between fast 125ms and slow 1s integration Not applicable to the LCR meter 8 3 USING THE MULTI METER The first application of the Multi meter has been described in section 3 4 1 when CLIOwin was started for the first time This was a simple generation of a 1kHz sinusoid OdBu output level and relative level capture with the Multi meter You can continue the measurement described to familiarize better with the instrument Pressing the magnifier will let you inspect all the parameters that the Multi meter measures in parallel Fig 8 1 changing the selected parameter will bring it in foreground for any parameter it is possible to choose different units for example THD can be shown in percentage or in dB then you can select the input channel and the integration This last parameter integration affects the measurement rate since the integration fast assumes 125ms of exponential averaging while the integration slow assumes 1s of exponential averaging The program approximates these constants trying to measure the computer speed and varying the number of averages calculated The rest of the paragraph deals with other applications of the Multi meter 8 3 1 CONTROLLI NG THE GENERATOR It is possible to control the generator by means of the dedicated main toolbar button 70 Chapter 8 Multi Meter di ina way as an on off switch works please refer to 5 4 3 for details Here itis possible to con
131. ther useful signals are noises and multitones The predefined signal file is the all4096 sig you can play it pressing the FILE button from the Multi meter panel or choosing It from the list of signal files As its name suggests this multitone signal is done adding 4096 sinusoids of the same amplitude which frequencies exactly fall inside an FFT frequency bin for a sampling frequency of 51200Hz a frequency bin ina 4096 points analysis is a multiple of 12 5Hz for a sampling frequency of 48000Hz a frequency bin in a 4096 points analysis is a multiple of 11 71875Hz This particular signal should be employed for maximum performances when analyzing a system with a 4096 points FFT should you change FFT size you should change stimulus too Using this signal it Is possible to assess the frequency response in a single FFT acquisition without the need for any averaging Among noises we find the pink noise that is required when taking RTA measurements CLIOwin has several pseudo random pink noises like pink16384 sig that are filtered versions of an MLS sequence Use this stimulus when executing RTA measurements due to its pseudo random nature permits RTA analysis that settle in a fraction of time with respect to analysis done with true pink noise Choose the file with the name matching the length of the FFT used for a 16K RTA use the pink16384 sig signal The main application of RTA analysis is in assessing the quality of an audio installation from the pl
132. thinking in terms of octave or fraction of octave which are the terms of a logarithmic frequency axis 3 125Hz is around 1 2218 of an octave at 10kHz while is around 1 3 of an octave at 10Hz Again one example is better than one thousand words We will measure a twin T notch filter probably the most demanding situation for frequency resolution with two sizes 8k and 64k and two centre frequency 10k and 63Hz Results are in Fig 10 7 20 0 180 0 dBV Deg 108 0 NI Ui Tt 20 0 40 0 60 0 108 0 180 0 Figure 10 7 Interestingly the measurements are four but we can see only three curves In fact the 8k size gives by far enough resolution at 10kHz and the relative curve is completely hidden by the 64k one At 63Hz instead the 64k curve red differs from the 8k blue We have seen that there is another parameter involved here which is sampling frequency While experimenting with it we will also make our first impedance measurement We will use CLI O internal mode This is again the default setting so all we have to do is to change the Y scale unit to Ohm We are going to measure a big 15 professional woofer using 51 2kHz and 6 4kHz leaving size at 16k The output level is set at 12dB Fig 10 8 and 10 9 shows the results Chapter 10 MLS 91 180 0 150 0 Deg Ohm 108 0 120 0 36 0 90 0 108 0 30 0
133. ting in clear evidence frequency zones where the polar response is acceptable and others where it Is not Figure 12 18 126 Chapter 12 Waterfall 13 MEASURING IMPEDANCE AND T amp S PARAMETERS 13 1 INTRODUCTION This chapter deals before going in the Thiele and Small Parameters Menu description with impedance measurements in general CLIO performs impedance vs frequency measurements both from within the MLS and the Sinusoidal Menu You will find specific information in the relative Chapters Both are relevant to what we will explain now Here we explain connections principles and other topics that apply to both menus Differences and choice criteria are also covered 13 2 GENERALS Whatever the stimuli CLIO sees a voltage at its input Impedance is obtained by a Suitable post process which changes upon how user decides to perform the measure ment Four methods are available Two of them Internal and I Sense were already found in the Settings Dialog both in MLS and Sinusoidal We will start with these leaving Constant Voltage and Constant Current to later on The last two methods derive their name from the description of what is going on during the measurement they were the standard before automatic computer based Measuring Systems Internal and I Sense are faster require only one measure it is easier to handle the connections needed 13 3 INTERNAL MODE INPUT A CLIO INPUT B OUTPUT A OUTPUT B Figure
134. tions cv function and ci function are explained in Chapter 13 as they are impedance tools 20 100 1k Hz 10k 20k Chapter 10 MLS Figure 10 38 103 104 Chapter 10 MLS 11 SINUSOIDAL 11 1 INTRODUCTION Within Sinusoldal it is possible to carry out Frequency Response Analysis Impedance Analysis and Distortion Analysis As should be obvious the stimuli used is a Sinusoidal signal stepped swept within user defined Frequency limits Although Sinusoidal steady state analysis is among the oldest and more traditional kind of measure CLIO merges the reliability of this well known technique with the power of advanced DSP The completely programmable Gating feature allows to add quasi anechoic Frequency Response capability 11 2 SINUSOI DAL CONTROL PANEL EI Sinusoidal Biel x 1k Hz Filename CHA dBY Unsmoothed Stepped Delay ms 0 000 Dist Rise dB 30 00 4 Chapter 11 Sinusoidal 105 11 2 1 TOOLBAR BUTTONS EN Starts the sinusoidal measurement HIT pressed the measurements will be autosaved The current autosave definitions Me I M apply see 6 3 1 for details Automatically applies the defined post process after the measurement has been taken Displays the phase response instead of modulus response Enters the Sinusoidal Post Process Dialog described below Enters the Sinusoidal Setting Dialog des
135. tivity in mV Pa of the microphonic front end and store it in the CLI Owin settings Le Jaen Affa Sl FJ FILE Reset Microphone Sensitivity 14 Um Za Figure 8 6 If you press the button s drop down you see reported the actual Microphone sensitivity In this case differently from the case of Voltage measurements the default quantity is 18 mV Pa which is a rough average or Audiomatica s microphones MI C 01 and MIC 02 sensitivity Let s see how to capture the channel A microphone sensitivity In Figure 8 7 you see a Bruel amp Kjaer 4231 acoustic calibrator fitted to a MIC 02 microphone Chapter 8 Multi Meter 73 Figure 8 7 With the Multi meter running fit the calibrator in place and switch it on Wait some second for the measurement to stabilize Then press the button You will receive the prompt in Fig 8 8 Warning AN fou are about to change Microphone Sensitivity Continue Figure 8 8 Be advised that answering yes you will affect all pressure measurements executed with input channel A You can inspect the newly acquired sensitivity entering the microphone sensitivity dialog see 5 4 4 8 5 THE LCR METER This is a particular operating mode of the Multi meter that gives you the possibility of measure inductors capacitors and resistors This measurement is an impedance measurement and is carried out in the Internal Mode please have Chapter 13 as a reference for what concerns impedance relat
136. trol the generation of single signal types and quickly pass from one to another When the generator control toolbar is active the following buttons are available SIN Generates the currently defined sinusoid The default sinusoid is 1031 25Hz continuous 2SIN Generates the currently defined two tones signal The default is1031 25Hz 2062 5Hz 50 each MLS Generates the currently defined MLS sequence The default is a 16383 MLS sequence WHITE Generates a white noise signal It plays the white sig file PINK Generates a pink noise signal It plays the pink13 sig file FI LE Generates the currently defined signal file The default is the all4096 sig file SET Enters the generator drop down menu to define the signals played by the various buttons See 5 4 3 for details 0 1dB Increases the output level by 0 1dB Equivalent to SHIFT F8 or SHIFT a main toolbar button 1dB Increases the output level by 1dB Equivalent to F8 or the main toolbar button 1dB Decreases the output level by 1dB Equivalent to F8 or the we main toolbar button 0 1dB Decreases the output level by 0 1dB Equivalent to SHIFT F8 or SHI FT main toolbar button 8 3 2 THE MI NI MI ZED STATE It is possible to operate the Multi meter in what we call a minimized state Pressing the relative button the control panel collapses and in its place remains a stay on the top display as in Fig 8 2 x 0 775 Vrms Figure 8 2 Chapter
137. ts to it Maintain the instrument connected as in Fig 3 9 with input A and output A short circuited Press the MLS button to start generating the MLS signal the same that MLS uses during its operation Press Go to start acquiring this signal you should read circa 0 54V Select also the Slow integration as the MLS signal is a wide band noise While D D PF i D D the measurement is running press the button answering yes to the warning message you ll set the global reference level To inspect the captured value press the button s drop down menu You should see the situation in Fig 8 4 B i Multi Meter 10 x ti x rnr i Voltage 2 vims sl Sioux ETE av I BC SN 2SIN MLS mme PNK FILE Reset 0 10B Reference Level 0 545 O e 5 4 5 Vrms Filename E Figure 8 4 The drop down tells you what is the actual global reference level If you want to restore the default which is 1V just choose Reset Should you choose now as reading units dBRel expect to read OdBRel 72 Chapter 8 Multi Meter But let s go to the MLS control panel and see how we can reference frequency response measurements Open the MLS control panel and simply choose dBRel as units Then execute the measurement You should obtain the situation of Fig 8 5 as general tendency is always a Straight line but the reading now is circa OdBRel BJ MLS Frequency Response 10 x Tico e zeit Ha zap Flunsmocthes CO 00 4 a
138. ut side effects those above are problems free settings for impedance measurements We will experiment a little pointing out difficulties that might arise Lets start with output level which is a sensitive topic 128 Chapter 13 Measuring impedance and T amp S parameters 13 3 2 SETTING THE RIGHT LEVEL The five curves of Fig 13 4 are taken at 5 different output levels ranging from 10dBu to 10dBu in 5dB steps The red curve refers to 10dBu the blue to 5dBu the remaining are substantially overlapped 25 0 180 0 Ohm 15 0 10 0 Figure 13 4 It turns out that going from linear device to loudspeakers makes the life harder even if probably more interesting Deriving the principals TS Parameters from the five curves yields to Table 13 1 ep Jus kee lossas Joen Table 13 1 Values from OdBu to 10dBu are in optimum agreement and this set the maximum level to be used to OdBu Interestingly enough Internal Mode is the less sensitive to output level We will go further on this topic relaying on CLIO being a complete and powerful audio measuring system Without changing connections we will use CLIO s FFT and Signal Generator to evaluate the distortion current at resonance at 10dBu Fig 13 5 shows the spectrum in this condition The second harmonic is 56dB lower than the fundamental which is 0 158 distortion Even at 10dBu we are by far in the linear region of the loudspeaker motor However what we have seen above clearl
139. vel has became 17dBV now We change connections accordingly with Fig 13 17 and nothing else INPUT A INPUT B CLIO OUTPUT A OUTPUT B POWER AMPLIFIER Figure 13 17 Chapter 13 Measuring impedance and T amp S parameters 135 The figure shows us we are going to measure the voltage across the device Therefore the next graph Fig 13 18 will give us detailed information regarding the measuring level CLIO 30 0 108 0 Figure 13 18 The level is low enough not to worry us and we proceed with our post process as before Instead of the CV button CI should be selected GH ka NL ch lh D File R Ohm Jong FileMame cireference sin Browse Cancel CLIO 10 100 1k 10k 108 0 180 0 Ok Figure 13 19 13 6 IMPEDANCE SINUSOIDAL OR MLS Up to now we have nearly only used Sinusoidal to perform Impedance Measurements When MLS has been used it was to point out problems We also stated Sinusoidal is the preferred choice Inexperienced user might ask why the MLS Menu has impedance measuring capability at all In fact MLS yields to accurate Impedance Measurements It is however less prone to forgive errors and or measuring set up problems of any 136 Chapter 13 Measuring impedance and T amp S parameters
140. vity display amp control buttons Displays the actual input sensitivity in dBV of the instrument i e the voltage level beyond which the board saturates It is possible to modify it in 10dB steps pressing the or F9 and a or F10 buttons e Selects the Autorange mode When in autorange the input sensitivity is automatically adjusted by the instrument to achieve the optimum signal to noise ratio 5 4 5 MICROPHONE CONTROL Ty Switches the phantom power on and off This 8 2V supply is needed to operate Audiomatica s microphones MIC 01 and MIC O2 gr Enters the Microphone Sensitivity dialog box Chapter 5 CLI Owin basics 43 Hicrophone Sensitivity CHA Mic Sensitivity mv Pa 17 00 CHB Mic Sensitivity mv Pa 17 00 CHA Mic Correction M CHB Mic Correction I Cancel Fig 5 5 Microphone sensitivity dialog When taking acoustical measurements the readings and the scales will be in Pascals Pa or dBSPL In this case the software will assume that you are measuring a pressure quantity and it therefore needs to know a conversion factor that defines the voltage produced by the microphone when it is measuring a certain pressure This conversion factor is usually the sensitivity of the microphone as found in the microphone s calibration chart or the sensitivity of the microphone preamplifier chain of equipment When working with the CLIO system there are two possible cases a you are using the microphone MIC 01 or MIC 02
141. vokes the On Line Help 52 Chapter 5 CLI Owin basics 5 7 BASIC CONNECTIONS In order to correctly interface CLIO with the outer world you should always keep in mind the following electrical specifications MAXIMUM INPUT VOLTAGE 40 dBV 283 V peak to peak MAXIMUM OUTPUT VOLTAGE 12 dBu 3 1 Vrms sine INPUT IMPEDANCE 64 kohm OUTPUT IMPEDANCE 150 ohm 5 7 1 CONNECTI NG THE CLI O BOX The CLI O Box has four RCA plugs that are used to connect it with the outside world Fig 5 21 The left ones are the two input while the right ones are the output The system is stereo and can simultaneously process two I O channels which are named channel A and B The output of channel B is driven in parallel with channel A output CLIO AN e ir OV Figure 5 21 Se The software is able to analyze either the signal present at channel A or channel B input in an unbalanced configuration or the combined A B signal thus realizing a balanced input configuration Fig 5 18 inthe firstcase the input connection can be realized with one simple RCA cable while in the latter case it is mandatory to realize a balanced probe that will connect channel A input used as the positive or hot to the first measuring point channel B input used as the negative or cold to the second measuring point and ground INPUT A INPUT B C L lO OUTPUT A G OUTPUT B Figure 5 22 WARNING Both CLIO inputs and outputs are r
142. ware control via the parallel port of the PC A dedicated output ISENSE allows impedance measurements in constant voltage mode as well voice coil current distortion analysis A dedicated input permits an external foot pedal switch to be connected and trigger QC operations 2 4 1 TECHNICAL SPECI FI CATI ONS Inputs Four line microphone inputs with selectable phantom power supply 8 2V One TTL input for external trigger Functions TTL controlled internal switches for impedance measurements Output power 50W 80hm with current sensing THD 1 kHz 0 004 Dimensions 23 w x23 d x4 h cm Weight 1 4kg AC 90 240V 18 Chapter 2 The CLIO System 3 CLIO INSTALLATI ON 3 1 MINIMUM PC CONFI GURATI ON The CLIO PB4281 PC board and its companion SC 01 Signal Conditioner running the CLIOwin software can be installed in any IBM or compatible personal computer with the following minimum system requirements Pentium processor suggested minimum 166 MHz One free PCI slot One free RS 232 serial port 32 MB RAM 800x600 256 color video adapter Microsoft Windows 95 98 ME 2000 or XP Microsoft Internet Explorer 4 01 Adobe Acrobat Reader 4 3 2 HARDWARE INSTALLATI ON 3 2 1 INSTALLI NG THE PCI CARD To install the CLIO PB4281 card in your computer you should follow the instructions given below 1 Disconnect the mains power cable from the PC 2 Open the computer cabinet 3 With the motherboard in front o
143. we deal with a tweeter we will consider the 2k 20k frequency range where the marker reads a constant 2 01ms We will use this value to operate a time shift that removes the time of sound fly This is accomplished from the Processing Tools Dialog selecting Time shift and 110 0 7 50 ms 6 00 4 50 k Hz 60 0 10k 20k 50 0 00 20 100 1 Figure 10 25 typing the value we found as in Fig 10 26 Clicking Ok we can finally display the processed phase minimum phase and magnitude response of our device in Fig 10 27 We used the term processed phase here and this SFX wR ONG Value Time ms 12 01 Ok Cancel Figure 10 26 IS not casual 98 Chapter 10 MLS Figure 10 27 To terminate this difficult paragraph we will summarise what we did with some comments Measuring acoustic phase response is often far from a press a button and get it procedure We went trough several phase plots all looking different but this is an important point all correct It is common to identify the processed phase as the true one only because it looks better It is important to stress that the true phase is that of Figures 10 18 and 10 19 CLIO intended as a computer based instrument can as we will see later easily calculate the summed response of woofer and tweeter after their are taken separately but with the same microphone position What we did with our complicated procedure was to obtain a response as i
144. y states 10dBu are a quite high level for this device Chapter 13 Measuring impedance and T amp S parameters 129 Figure 13 8 Reader could be tempted to determine absolute quality of the device by means of this procedure While he or she may be right a lot of experience is needed One important parameter for reliable comparison among devices is the value in VRMS at the speaker terminals at resonance It is shown from FFT as 10dBV that are 0 316VRMS 13 3 3 DEALING WITH ENVIRONMENTAL NOISE The next problem in measuring loudspeaker impedance is noise Transducers do their job in both directions and noise will appear as voltage exactly where CLI O s input is connected To evaluate the problem we deliberately produced a disturb generating a 110Hz single tone causing 58 dBSPL at the speaker cone We took two impedance curves In this condition one with MLS the second with Sinusoidal Both were taken at 10dBu a value that gained our favor before Results are in Fig 13 6 for MLS and Fig 13 7 for Sinusoidal CLIO 5 0 Ko 108 0 en 0 0 180 0 on 20 100 1k Hz 10k 20k 10 100 1k Hz 10k 20k Figures 13 6 and 13 7 This is one reason why we prefer sinusoidal analysis to measure impedance 13 3 4 DEALING WITH VIBRATIONS

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