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1. LEAP TS parameter calculation results for the MW16R were reasonably close to the factory data however my data definitely showed a lower V compared to the factory data Although the preliminary eco data showed some variation I followed my usual protocol and proceeded setting up computer enclosure simulations using the LEAP LTD parameters for Sample 1 Two computer box simulations were programmed into LEAP one sealed and one vented This resulted in a 0 5 ft sealed enclosure with 50 fiberglass fill material and a 1 0 ft QB3 vented enclosure with 15 fiberglass fill material and tuned to 30 Hz Figure 11 displays the results for the SB Acoustics Satori woofer in the sealed and vented boxes at 2 83 V and at a volt age level sufficiently high enough to increase cone excursion to Xmax 15 6 9 mm for the MW16R This produced a F frequency of 58 Hz with a box driver Ote of 0 69 for the 0 5 ft sealed enclosure and 3 dB 40 Hz for the 1 0 ft vented simulation Increasing the voltage input to the simula tions until the maximum linear cone excursion was reached resulted in 101 5 dB at 14 V for the sealed enclosure simula tion and 103 dB with a 13 5 V input level for the larger vented box see Figure 12 and 13 for the 2 83 V group delay curves and the 14 13 5 V excursion curves Klippel analysis for the SB Acoustics 6 5 woofer our ana lyzer is provided courtesy of Klippel GmbH performed by Pat Turnmire Red Rock Acoustics
2. Preview all pages View a list of archived issues Flip to the cover Flip to the previous page Flip to mthe next page Flip to the back cover Search Print Download entire pdf Toggle full screen Help guide Close Products amp Services Index CATEGORY KEY A ADHESIVES B CONSULTANTS amp ENGINEERS C CROSSOVERS amp PASSIVE COMPONENTS DRIVERS EMPLOYMENT OPPORTUNITIES ENCLOSURES amp ENCLOSURE PARTS ENGINEERING DESIGN SOFTWARE FINISHED SYSTEMS Advertiser NTI Americas AGO Pan One Magnet Electronic Co Ltd sues 17 Audience Precision Econowind Inc Prism Media Products Pulsus Technologies Categories audioXpress Beston Technology Corporation BMS Speakers GmbH Rotel Electronics e ea eee Consumer Electronics Association CES Faital USA Materion Electrofusion BEO Menlo Science B Ningbo Yinzhou Huada Sound Solen Electronique Inc ED Speaker Design Consultants Tang BandIndustriesCo D Vance Dickason Voice Coil Wavecor ltd A a eiat F H This product services index is provided as a value added service to our readers and advertisers The publisher will not be held liable for any errors or deletions contained herein S MAGNETS amp EQUIPMENT MANUFACTURING EQUIPMENT MICROPHONES PARTS RECONING TEST EQUIPMENT VOICE COILS COMPONENTS amp MATERIALS TRANSDUCERS ACOUSTIC MESH ACOUST
3. the company said Frequency response is rated at 57 Hz to 23 kHz 3 dB but usable bass is said to go down to 47 Hz The speaker comes in high gloss piano black enclosure with a front that curves on both sides and dark tint tempered glass base The speaker also features a USB port to charge handheld USB connected Apple devices and play their music A 3 5 mm analog input connects to other portable devices to play back their music The Klipsch Gallery G 17 Air streams music via Wi Fi network MEN voice co MK Sound Exhibits Several New Products MK Sound exhibited a number of new products at the September CEDIA Expo with its first floor standing speaker first flat on wall speaker intended for use with flat panel TVs and an addition to its in wall speaker series The com pany also displayed three new powered subwoofers In its Architectural series of speakers the company added its first in ceiling model to its current selection of three in wall speak ers without bezels The new IW5 features 4 midbass driver and 1 neodymium dome tweeter with choice of square or round magnet mounted grilles which are white and paint able It also features spring loaded terminals with polarity markings steel front baffle and acoustic signature designed to match the MK Sound M series of in room satellites It will join two way models with 5 25 and 6 5 woofers all of which feature the company s proprietary Phase Focused crossover design to ensur
4. 10 dB Other features include analog aux input headphone output and IR remote that controls system volume as well as such iTunes and portable device functions as play pause and skip forward back Klipsch Offers New AirPlay System Klipsch plans fall availability in the U S of its first AirPlay enabled tabletop speaker system and an expanded headphone selection which includes the brand first headphone series targeted exclusively to A V specialty stores The products will be displayed for the first time at the IFA show in Berlin In releasing more details about its long awaited AirPlay speaker the company priced the Klipsch Gallery G 17 Air at a sug gested 549 Klipsch also revealed that the thin speaker system is not only Apple AirPlay compatible but also streams music via Wi Fi network from handheld Android devices equipped with third party DLNA capable music player apps As an AirPlay compatible speaker the G 17 Air streams music from a home s Wi Fi network from handheld Apple iOS 4 2 devices and from a PC s iTunes application When streaming music from iTunes consumers can control song selection by using their Apple handheld device as a Wi Fi remote The 6 x 6 9 x 3 5 speaker which is also wall mountable is a biamplified two way stereo speaker system with two ported 2 5 woofers and two 0 75 tweeters which are loaded in square Tractrix Horns Total amplification of 60 W deliv ers output of 102 dB in a typical room
5. Enhance Your system s Sound Quality Fully Optimize Your Digital Dock With These Iwo Chips PS5331 PS6141 190 DMIPS Highly extensive post processing without external memory Mental Pure digital streaming from iPod iPhone iPad skino TDMA free transmission x oni na SRA EEN MES j DIR field proven PWM SRC LY Bed MICOM ON Hardwired sound processor a USB host controller No additional MICOM or USB PHY needed Integrated MICOM interface for DSP amp PWM A Ready to use highly stable software and dnvers GUI We Remote firmware update capability 2Post ia ATO initia PAN dci lea Supports USB thumb drive with media decoding Jrocessing Pro audio algorithms a meleri Real time alarm clock power management Ul etc Et Decoding Dolby AC3 etc js More High quality Solutions for N Home Theater Soundbar Headphones Computer Speakers rar iii Hene Avoailahia Premium ODM Serv ices AvalilanDlie m E p dE wal aa Ave dm 4 r gi ib gd gl la sir international i ale a5 0 pulsi us CO KI www pu isi TEM e g m 1 Uo orig an me clea andre Tel shift SE ale gt COM 800 565 4390 NX voice com remaining alert for new worldwide opportunities e Capability to manage the financial affairs of the Society and sustain AES viability e Computer literacy and a business knowledge e The ability for frequent travel national and global in support of AES objectives and external alli
6. NTI China NTI Japan Suzhou Beijing Shenzhen Tokyo Japan 86 512 6802 0075 81 3 3634 6110 www nti audio com Lighter Stiffer Faster Genuine Beryllium for Maximum Value ODM Applications and Direct Replacement truexlrenT ADVANCED ACOUSTIC TECHNOLOGY MATERION www truextent com 44036 South Grimmer Blvd Fremont CA 94538 1 510 661 9755 truextent materion com Truextent is a registered trademark of Materion Brush Inc left right balance stereo mode front rear balance surround mode To download a free copy of How to Listen software and and the ED is required to conduct the business of the Society at this office The ED shall devote best efforts attention and energies to the business of the Society and during the term of employment may not engage in any other business or occupa VOICE m Voice Cotl ISSN 1521 091X the Periodical of the Loudspeaker Industry is published monthly by Segment LLC 4 Park St Vernon CT 06066 USA 860 875 2199 user manual visit the website at www harmanhowtolisten blogspot com Call for Applications AES Executive Director The Audio Engineering Society Inc AES is seeking appli cations for the position of executive director employment will begin on January 1 2012 The AES is the only professional society devoted exclusively to audio technology Founded in the United States in 1948 the AFS has grown to become an
7. PLA l ii pp Better i AS gt mple to Y s SOFTWARE igner s SPEAKER Ofer Col tal ee t 75 ias si s 24 s 75 SPL vs Freq NOVEMBER 2011 Response and Harmonics Fundamental L m Harmonic 2 L Paia Harmonic 3 L an 130 SPL dE re 04 Pa qu a l 50 100 1000 10000 20000 Frequency Hz ae THD L a 4 3rd Harm Dist L Pai A New het z l 1000 10000 Hz Figure 22 SB Acoustics MW16R SoundCheck distortion plots with a small amount of anomalous behavior up to the low pass roll off beginning at 16 kHz Figure 20 displays the on and off axis frequency response at 0 15 30 and 45 At 30 3 dB with respect to the on axis curve occurs at 2 8 kHz so a cross point at 3 kHz or lower would be appropriate And finally Figure 21 gives the two sample SPL comparisons for the 6 5 SB driver showing a close match to within 0 5 dB throughout the operating range For the remaining group of tests I employed the Listen Inc SoundCheck analyzer and SCM 0 25 microphone courtesy of Listen Inc to measure distortion and generate time frequency plots For the distortion measurement the Satori woofer was mounted rigidly in free air and the SPL set to 94 dB at 1 m 5 6 V using a noise stimulus and then the distortion measured at with the Listen Inc microphone placed 10 cm from the dust cap This produced the distortion curves shown in Figure 22 I then used SoundChec
8. about 0 1 mm at the rest position and transitioning to 0 1 mm coil out offset at the physical Xmax position Looking at both sets of data Bl and compliance the conclusion is likely that the coil is about 1 mm offset from magnetic center I say this ES ES eS ee SSeS ee a because that is the offset at a place of strong certainty in the measurement at 7 mm Displacement limiting numbers calculated by the Klippel analyzer for the MW16R were XBl 82 BI 4 9 mm and for XC 75 Cms minimum was 4 6 mm which means that for this Vifa woofer the compliance is the most limiting factor for prescribed distortion level of 10 Figure 18 gives the inductance curves Le X for the Satori 6 5 Inductance will typically increase in the rear direction 2 A ee oe oe ee le Figure 10 SB Acoustics MW16R woofer free air impedance plot SPL vs Freq from the zero rest position as the voice coil covers more pole area which is what you see in the MW16R Le X curve however the variation is only 0 20 mH to 0 15 mH from the in and out Xmax positions which is very good Next I mounted the MW16R woofer in an enclosure which had a 13 x 6 baffle and was filled with damping material foam and then measured the DUT on and off axis from 300 Hz to 20 kHz frequency response at 2 83 V 1 m using the LinearX LMS analy
9. all what we want It is clear that some thing is causing cancellation We know that the acoustic Linkwitz Riley response of each device should sum to a flat response Since it doesnt this would seem to indicate the problem is a misalignment of the two devices in the time domain Looking at the Envelope Time Curve ETC of the passbands see Figure 4 confirms that they are not synchro nized We need to delay the cluster but by how much If we choose to align the clusters peak arrival with the peak arrival from the subwoofer we need to delay the cluster 14 7 ms Alternatively we might choose to try to place the arrival of the cluster more towards the leading edge of the subwoofers ETC This will require approximate 10 ms of delay for the cluster The frequency and time domain of both these scenarios are shown in Figure 5 and Figure 6 Neither of the frequency domain curves looks like what one would consider good summation reasonably flat response The time domain would seem to indicate that the shorter delay is closer to the ideal response than the longer delay We could go on guessing at different delay times in an attempt to optimize the response in both domains Hopefully there is a better way The underlying problem is that we have only low fre quency information output from the subwoofer From the equation at Af where At is time resolution and Af is frequency resolution we can see that high frequency resolution small value
10. author of the SpeaD and RevSpeaD software produced the BI X Kms X and Bl and Kms symmetry range plots given in Figures 14 to 17 This data is extremely valuable for transducer engineering so if you dont own a Klippel analyzer and would like to have analysis done on a particular driver project Red Rock Acoustics can provide Klippel analysis of almost any driver for a nominal fee of 100 per unit for contact information visit the Red Rock Acoustics website at www redrockacoustics com The BI X curve for the MWTGR see Figure 14 is fairly broad and but obviously with a component of asymmetry with a forward coil out offset Looking at the Bl Symmetry plot see Figure 15 this curve shows a 3 4 mm coil forward offset at the rest position that decreases to 1 mm at the 7 mm just beyond the physical Xmax for this driver One of the things have not talked about very often is the grey area on the graph _ This represents the area of uncertainty for the analyzer Since Bl curves are typically flat until you reach the knee where Bl begins to decrease it is difficult to resolve exactly what is happening to the motor system Figure 16 and 17 show the Kms X and Sample Submissions for Test Bench Test Bench is an open forum for OEM driver manufac turers in the industry and all OEM s are invited to submit samples to Voice Coil for inclusion in the monthly Test Bench column Driver samples can be for use in any sector of the lo
11. cap shorting ring on the vented pole silver alloy lead wires terminating to gold terminals and a cast alumi num faceplate SB also offers a slightly lower cost version with an injection molded plastic faceplate the SB26STC Testing commenced using the LinearX LMS analyzer to produce the 300 point impedance sweep illustrated in Figure 1 The magnetic fluid damped resonance occurs at a moderately low 731 Hz With a 2 96 Q DCR the minimum impedance for this tweeter is 3 1 Q at 2 1 kHz Following the impedance test I recess mounted the SB tweeter in an enclosure that had a baffle area of 10 x 8 and measured the on and off axis frequency response with a 100 point gated sine wave sweep at 2 83 V 1 m Figure 2 shows the on axis response to be a very flat 2 05 dB from 1 kHz to 13 kHz and from 1 kHz to 29 kHz 3 1 dB Figure 3 depicts the on and off axis response of SB26STAC with the off axis curves normalized to the on axis response in Figure 4 The two sample SPL comparison is illustrated in Figure 5 indicating the two samples were closely matched with a small 1 dB variation between 4 5 kHz to 6 kHz The next test procedure was to fire up the Listen Inc SoundCheck analyzer along with the Listen Inc SCM 14 microphone provided courtesy of Listen Inc to measure the impulse response with the tweeter recess mounted on the test baffle Importing this data into the Listen Inc SoundMap software produced the cumulative spectral de
12. distance REVIEWER COMMENTS This is an excellent example of a patent that lays claim to an old useful concept but it is granted due to a special combina tion of circumstances This usually happens by way of one or more of three things 1 the patent examiner viewing only past patents but being unaware of audio development disclosed in the literature AES JASA etc 2 being assigned a patent examiner who is unaware of standard loudspeaker system design practice and 3 to have a skillful patent attorney who can effectively argue your case with the examiner and write claims that appear to differentiate but in actuality provide a very broad coverage A study of this simple case can be a good learning tool for those interested in how effective claims can be crafted and argued and also how naive the patent office can be relative to the field of loudspeaker prior art Disclosed is a pair of transduc ers mounted adjacent to each other and wired in series As the frequency of operation is increased and the wavelength of the drive frequency is a half wavelength or greater than the center to center separation of the two transducers a bypass capacitor is connected in parallel with one of the transducers so as to act as a low pass filter for that transducer This type of series driver arrangement with a parallel bypass capacitor can be very effective and elegantly economical in what it accomplishes in that with a single component it
13. not only creates a low pass filter for the one of the transducers it also level shifts the remaining transducer upward in output so as to maintain the same system output above and below the crossover frequency for a given input voltage For the levels between the two transducers to remain equal in their passband and the transition to work as perfectly as described requires that the two transducers are identical or that they at least have identi cal impedance curves and sensitivities at and near the crossover frequency When the crossover frequency is near the resonance frequency of the drivers with the usual associated impedance peak there will be an amplitude imbalance between the two drivers If used near the resonant frequency it works best with impedance smoothing networks or with transducers with substantially resistive impedance characteristics such as some planar magnetics But if used well removed from the resonant frequency this simple technique can be quite effective and eco nomical compared to the equivalent transfer function applied to two transducers in parallel As a side note not mentioned in the patent this technique can also be a very low cost and effective way to passively transition line source arrays of multiple drivers to maintain a Magnets that meet the highest of quality standards For magnets that adhere to the highest of quality standards work with us Conforming with ISO TS 16949 2002 standards our 20 i
14. range system crossover e The relative output level of the subwoofer and the full range system gain e The relative arrival time of the signal from the sub woofer and the full range system delay It is this last item that is perhaps the most challenging This is the one that we will primarily investigate We will also look at the first item briefly With these taken care of the second item should not be too much of a problem Loudspeakers by their nature are band pass devices To Figure 1 Magnitude response of individual simulated loudspeakers Firre cl ge er n roe Ti 1 NE CEC i ee eni Figure 2 Magnitude response of cluster without HP filter blue target Linkwitz Riley response green and cluster with HP filter red simplify the measurements and make it easier to see whats going on with the graphs I will use high pass and low pass filters instead of actual loudspeakers The results will be the same with one exception microphone location Since our examples dont use a microphone only electrical measure ments it cant be moved to a different location This can be much more critical for measurements at higher freguen cies because the directivity response of a loudspeaker will lead to differences in the measured response of a device at different locations For devices that are for the most part omni directional in the lower frequency region this will not be an issue There is another issue of which one shoul
15. speaker operably secured to a network for applying an appropriate frequency component of an electrical input drive EL61094 4 Compliant Long term Stability Temp and Humidity TN an a a Fertormnance Attention All hi fi audio consumer electronics electrical product buyers from the USA Europe Japan and the rest of the world For competent 3 4 m dependable prompt and cost competitive quality Now in Stocks assurance services in the Philippines and the rest of Asia please visit www qualityguru net for more 48 details 2 QUALITY GURU AUDIT amp INSPECTION SERVICES WHERE QUALITY IS NEVER AN ACCIDENT p6 03p00 2 0 03050 000 73 ho my j 7052PH MK224PH IC ACO Pacific Inc 2604 Read Ave Belmont CA 94002 USA Tel 650 595 8588 Fax 650 591 2891 www acopacific com sales acopacific com ACOustics Begins With ACO ETA voice com signal said speaker comprising a frame a pair of drivers oper ably secured to said frame and spaced apart from each other by a defined distance said pair of drivers configured to operate within substantially the same range of frequencies and con nected to the network a capacitor operably secured to one driver of said pair of drivers so as to gradually mute said one driver as a predefined frequency is approached by the network and a capacitance of the capacitor to gradually mute said one driver at the predefined frequency is a function of the defined
16. technique 3 S k D a First to use Hepta Litz seven strand insulated wire 2 Zero distortion air core lowest dc resistance 2 l p ea er esig n Widest range of values from 0 1 mH 30 mH C y Wide range of wire diameters from 0 8 mm 2 6 mm i on SU ta nts sound experience Contact us for the FREE 4470 Avenue Thibault Innovative Product Concepts Solen CDROM Catalog St Hubert QC Design from Concept through Manufacturing and Test was J3Y 779 Canada i Engineering Staff Mentoring Education and Growth ked with speak pac c with speaker Tel 450 656 2759 2 Critical Stage Design Evaluations and Solutions drivers hardware and se Improvement in Sound Quality Reliability and Consistency Fax 450 443 4949 i Design Optimization for Offshore Manufacturing crossover components Email solen solen ca including Solen brand Web wwwsolen ca MATA voice com Available ID DSP and EE Resources www spe consulta A 774 276 0691 the natural output of the cluster and the target Linkwitz Riley response along with the clusters output after it has been high pass filtered A 3 order Butterworth high pass at 115 Hz was used to get this response lower Fc and a parametric EQ filter might be used to achieve a more exact match The response shown will be close enough for our purposes When the outputs of the two devices are combined we get the responses shown in Figure 3 The summed magnitude response is not at
17. their continued enthusiasm and support Last and certainly not least 1 would like to add a special thank you to Edward T Dell for his vision and guidance that made this publication possible It was a great idea Ed Download Dr Sean Olive s Harman Listening Test How to Listen is a desktop software application devel oped by the Harman International R amp D group for the pur pose of training and selecting listeners used in audio product research development and testing The software consists of a number of training exercises where different kinds of timbral spatial and dynamic distortions commonly found E im is m Luna de ia a po fae Mam Goer BAND ID TRAINING TET Lis la ha Pha rl LG sl sl ech lara ee e Pree Guinn barg eed Figure 1 Band Identification illustrating peaks dips peaks and dips low and high pass filters performance Harman is offering a free beta version of this software to audio enthusiasts in the hope that they will use it to improve their critical listening skills and appreciation for high quality sound reproduction Features include support for two channel stereo and multichannel wav files up to 24 bit 96 kHz includes Session and Practice modes and cur rently supports two training tasks more will be added in the next release that include the following within the recording and audio chains are simulated and added to music The listeners task is to identify
18. were first time visitors and 83 of the 444 exhibitors were also there for the first time As the economy continues to struggle CEDIA attendance has unfortunately progressively declined over the last five years The 2010 CEDIA Expo in Atlanta attracted 20 700 visitors the 2009 CEDIA Expos attendance was 20 000 the 2008 show had 25 000 and the 2007 CEDIA Expo had 29 000 visitors THX Details Performance Standards THX revealed more details about its first performance standard for soundbars pointing out that active and pas sive models would qualify for its certification mark but that all would likely require the use of an active subwoofer The certification standard would join standards for A V receivers and HTIB systems The standard calls for flat response from 35 Hz to 20 kHz through a two or three channel soundbar reference sound levels of a minimum 85 dB with 20 dB of headroom at a viewing distance of 6 a smooth blend between satellite and subwoofer drivers and controlled horizontal and vertical dispersion to minimize distortion inducing floor ceiling and wall reflections The dispersion requirements would optimize sound reproduction for viewers sitting anywhere on a couch thats 6 from a TV The crossover level between subwoofer and satellite drivers is low enough to minimize location changes in voices and instruments The standard also calls for a minimum of two stereo analog connections Digital inputs are optional The standard
19. 011 e FS BN Ce Test Bench A New Tweeter and a New Woofer from SB Acoustics By Vance Dickason oth of the drivers submitted for this months issue are for home audio applications and both are from SB Acoustics SB submitted their SB26STAC C000 4 a fer rite motor 1 soft dome tweeter plus a new high end 6 5 midwoofer the MW16R Satori Test Bench has covered a number of SB Acoustics tweeters including the ferrite motor 29 mm ring dome SB29RDC C000 4 in the August 2009 issue its neodym ium 29 mm ring dome version the SB29RDNC C000 4 seen in the August 2011 issue and the SB26STCN C000 4 a 1 neo motor tweeter in the September issue of Voice Coil This months addition is the ferrite version of the SB26STCN the 1 SB26STAC C000 4 see Photo 1 It bears repeating that SB is the initials for Sinar Baja which is a large OEM driver manufacturer located in Indonesia However the driver line is the brainchild of David Stephens former U S representative of DST Keeping with his Danish driver heritage David is closely associated with former Vifa Scan Speak engineers Ulrik Schmidt and Frank Nielsen now co owners of Danesian Audio Danesian Audio does all the transducer engineering for SB Acoustics In terms of features the SB26STAC employs a 1 26 mm diameter treated cloth dome diaphragm a 1 underhung voice coil with 0 6 mm Xmax and wound with CCAW wire damped vented pole exhausting into a damped rear chamber a copper
20. E ca pe ON N Kin pm N DU ma 2 ca m j Th 8 1 ZE q Z WU a Y 7 e z ilg S 3 He 3 gt 1 a c m o oz ir o ta q oc o m YN H io ex gy Il l l l l l l l l 3 e os aa Eo ty me Him E i E amp E2 lt a ed noz 94 gF 145 a 5 Tes or a gt li E i E O SEL DT L o Tt il plot usually referred to as a Figure 6 Figure 7 is a Short Time Fourier Transform STFT displayed as a surface plot For the final test pro cedure set the 1 m SPL to 94 dB 4 2 V using a noise o stimulus and measured the 274 and 3 harmonic distor tion at 10 cm depicted in Figure 8 The next SB Acoustics driver is part of what assume will be a complete new series of ultra high end transducers for SB the Satori line So far there are only two drivers in this line the Satori TW29R similar to the SB29RDC C000 4 ring dome and the subject of this report the Satori MW16R see Photo 2a and 2b In the Zen Buddhist tradition satori refers to a flash of sudden awareness or individual enlightenment and is considered a first step or embarkation toward nir vana So to sport such an ambitious moniker I would expect the driver to be something special so lets get to it In terms of features the MW16P is built on a very cosmeti cally attractive six spoke frame somewhat resembling two other fairly recent entries into the high end driver market the Scan Speak Illumi
21. Fort Myers Florida 33903 Po Yun before it expires sin Phone 239 997 3860 Fax 239 997 3243 A For samples information or a quotation please contact Jon Van Rhee at jon precisioneconowind com Check your label to find the expiration date e ISO 9001 2000 e ISO 14000 e TS 16949 Renew annually online at Www voicecoilmagazine com vequal html www precisioneconowind com MOTA voice com We re thinking AN2075 50mm 2 AN2775 70mm 2 75 AN3510 88mm 3 5 CELESTION www celestion com e Acoustic Patents By James Croft Croft Acoustical he following loudspeaker related patents were filed primarily under the Office of Patent and Trademarks classification 181 for acoustical devices and 381 for electrical signal processing systems and HOAR for inter national patents This also includes new patent applica tions that are published in the Patent Application Journal SPEAKER WITH FREQUENCY DIRECTED DUAL DRIVERS Patent Number U S 8 005 240 Inventors Jason N Linse Portland OR Jeffery S Anderson Camas WA Filed May 23 2005 US Class 381 99 Granted August 23 2011 15 Claims 7 Drawings ABSTRACT FROM PATENT A speaker that includes a pair of spaced apart in plane mounted drivers connected in series to a network for applying the appropriate frequency component of the electrical input drive signal to each of the drivers is disclosed see Figure 1 Driver A Driver B Fig
22. ICAL amp SOUNDPROOFING MATERIALS AMPLIFICATION NOVEMBER 2011 sa dScope Series II Po TER Jit Prism Sound is now a global sales amp support agent for LOUDSOFT Loudspeaker design and analysis solutions electronic test acoustic test The dScope Series lll audio analyzer is the TE a te g ge te d fastest most capable test system available and incorporates a comprehensive suite of acoustic analysis tools including Gated impulse response Impedance Rub and buzz Loose particle detection From digital inputs to 125 interfaces through analog amplification to acoustic transducers test your entire system with a single instrument fast dScope Series Ill elale ele Ho slo Ke leJi el audio analyzers sales prismsound com www prismsound com USA 1 973 983 9577 UK 44 0 1353 648888
23. It will take place January 13 16 within the North Hall of the Las Vegas Convention Center an easy commute to The Riviera The ALMA Board of Directors in consideration of the program theme relating to the future of loudspeakers have committed to facilitating opportunities for knowledge sharing by paralleling the two programs and moving to this new loca tion The ICCE is where key technologies products services and architectures for consumer entertainment and informa tion delivery are first presented see www icce org for more information The 2012 ALMA Winter symposium will attract visitors and attendees from around the world and is a great opportu nity for manufacturers of components materials test equip ment and services to the industry to exhibit the latest products to the industry It is also a great opportunity for loudspeaker _ OEMs to meet with senior engineers and decision makers from United States loudspeaker companies who will be attending the show ALMA is happy to issue invitations to exhibitors and visitors from overseas and assist attendees with obtaining a visa Hotel rooms are blocked at The Riviera under the CES from January 6 15 and under _ ALMA International from January 13 16 For more information visit the ALMA International website at www almainternational org Linear X LF280 Precision Amplifier Filter r Attenuator The measurement of Class D and other PWM or Delta Sigm
24. V free air curves The complete data set the multiple voltage impedance curves for the LTD model see Figure 10 for the 1 V free air impedance curve and the 1 V Photo 2a The Satori MW16R top view b The Satori MW16R bot tom view Figure 9 SB Acoustics MW16R motor cutaway drawing TILL T The Must Have reference for gt loudspeaker engineering professionals Home Car or Home Theater Back and better than ever this 7th edition provides everything you need to become a better speaker designer If you still have a 3rd 4th 5th or even the 6th edition of the Loudspeaker Design Cookbook you are missing out on a tremendous amount of new and important information Now including Klippel analysis of drivers a chapter on loudspeaker voicing advice on testing and crossover changes and so much more Ships complete with bonus CD containing over 100 additional figures and a full set of loudspeaker design tools A 99 value Yours today for just 39 95 Shop for this book and many other Audio Amateur products at www cc webshop com Table 1 SB Acoustics Satori MW16R midwoofer Simi O md E lO amet Jsame2 sample E impedance curve for the TSL model were selected in the transducer derivation menu in LEAP 5 and the parameters created for the computer box simulations Table 1 compares the LEAP 5 LTD and TSL data and factory parameters for both of Satori MW16R samples
25. VOLUME Ss UTE NOVEMBER 2011 VOICE 4 COIL THE PERIODICAL FOR THE LOUDSPEAKER d Industry News and Developments By Vance Dickason Happy 25 Anniversary Voice Coll A Quarter Century of Loudspeaker Technology November 2011 marks the beginning of Voice Coils 25 year as an information resource for the loudspeaker industry Voice Coil magazine started with a conversation between Ed Dell and me following the Audio Amateur Inc publication of the 3 edition of the Loudspeaker Design Cookbook Ed related to me a concept of creating a publication that would become an information super highway for the loudspeaker industry Needless to say I considered it not only an outstanding con cept for a new publication but something I felt the industry badly needed and would happily support Obviously after 25 years we were both correct in moving forward with the pub lication Mr Dell came up with the name Voice Coil and as they say the rest is history From the first issue in November 1987 until June of 1995 Voice Coil was a monthly subscription based black and white four page newsletter that was written entirely by me with no INDUSTRY CELEBRATING other contributors and no advertising However the June 1995 issue jumped to 20 pages we are currently about 32 to 48 pages each month of four color printing on gloss paper and became advertiser driven with no subscription fee As we head into the era of digit
26. a digital modulator type output stage amplifiers such as a typical subwoofer amplifier often presents a problem due to _ high frequency switching noise components These high fre quency components can obstruct the measurement of in band typical 20 20 kHz measurements Many of these amplifiers have limited high frequency filtering of their own and many analyzers or other measuring instrumentation have inadequate filtering to remove the passband effects of these strong high frequency out of band components The LF280 offers a steep 80 kHz g order passive low pass filter see Figure 2 to remove these unwanted high frequency components and enable accurate in band amplifier response measurements The LF280 is constructed entirely of Moly Permalloy Powder MPP toroid inductors and Polypropylene capaci tors for the ultimate in stability high frequency performance reduction of high frequency loss and maximum linearity see Photo 1 The LF280 utilizes a combination of identical Where the next big thing meets the light of day Somewhere a back room conversation has caused a burst of inspiration And it will be unveiled here Come see a bright idea light the way to tomorrow PRODUCED BY Tuesday January 10 Friday January 13 2012 ie ns CEA Las Vegas Nevada CESweb org THE GLOBAL STAGE FOR INNOVATION REGISTER NOW components to reduce component sensitivity and produce a highly stabl
27. ability to listen to act and to stand behind decisions e Ability to recognize and effectively deal with AES increasing global and multicultural responsibilities while ADVERTISING For advertising reservations contact Strategic Media Marketing Inc 2 Main St Gloucester MA 01930 USA Phone 978 281 7708 or Fax 603 924 9467 Toll free 800 454 3741 e mail peter smmarketing us E mail Erica Fienman with artwork inquiries at advertising audioXpress com Qualified subscriptions to Voice Coil run for one year Renew annually on line at voicecoilmagazine com vcqual html Subscriptions to Voice Coil are available in printed and digital versions To subscribe to the digital version please visit our website at www audioXpress com and complete a qualification form When you qualify you will receive an e mail confirming your subscription The current issue of each digital Voice Coil will be posted to www gotomyvoicecoil com at the end of the month To access use the link in the e mail notification or you can simply log in to the website to view your issue along with the archived issues For questions relating to the digital issue please go to the help page at www audioxpress com digital_issue_help htm For those overseas the cost of a printed subscription is 150 00 per year Please contact customer service or order your subscription online at www audioXpress com Hi fi Digital Docking Solution Truly
28. akers two timbre matched center channels one dipole surround speaker and a dual driver 500 W subwoofer Prices of the left right speakers range from 1 199 pair to 4 999 pair a step above the Q series prices of 499 1 599 pair Reference prices are 10 000 20 000 pair Altec Lansing Releases a New Speaker System Altec Lansing releases retail availability of its first AirPlay enabled tabletop speaker system the inAir 5000 Although the company didnt reveal pricing here at the IFA show the company did reveal key specifications and features including tri amplification and a USB port that charges and plays back music from USB connected iPods iPhones The Altec Lansings inAir 5000 an AirPlay enabled tabletop speaker system NOVEMBER 2011 ENS and iPads With AirPlay however consumers dont have to physically connect their portable Apple devices to play back stored music The inAir 5000 uses AirPlay to wirelessly stream music via Wi Fi 802 11b g from an iPhone iPad or iPod touch AirPlay also enables the device to stream music wirelessly from a networked computers iTunes application The device boasts 110 W of amplification DSP two soft dome 1 neodymium magnet tweeters two 3 Kevlar cone tweeters one 4 woofer and one passive bass radiator Its curved chassis measures 7 5 x 19 x 6 75 and its non parallel walls prevent internal standing waves that generate distortion Frequency response is 50 Hz to 20 kHz
29. al delivery Voice Coil just this year became available as an Internet delivered subscription Besides the change in printing distribution and digital delivery Voice Coil began to include other contributors such as Wolfgang Klippel Steve Temme Jim Croft Mike Klasco Pat Turnmire Charlie Hughes Steve Mowry and many others over the years Support has come not only from some of the industries finest engineers but by the generosity of analyzer software manufacturers Klippel GmbH LinearX and Listen Inc who have supplied Voice Coil with some of the best test equipment available As this loudspeaker industry magazine has grown and matured Voice Coil continues to be what its originator and former publisher Ed Dell conceived it to be a world class clearing house of information for loudspeaker engineers manufacturers marketing specialists and OEM suppliers Evidenced by the participation of writers advertisers and readers Voice Coil continues to be well received by the entire loudspeaker industry Each year has brought increased circu lation as more engineers technicians purchasing agents and marketing experts discover what we have to offer On behalf of myself Vance Dickason editor Hugo Van haecke pub lisher C J Abate editorial coordinator Shannon Becker editorial assistant and all of the new staff at Audio Amateur who make this publication possible we would like to thank all our readers and advertisers for
30. ances All submissions must be submitted online at www aes org Any questions may be addressed to EDsearch201 1 aes org ALMA 2012 Symposium The Future of Loudspeakers ALMA the International Loudspeaker Association Winter Symposium program The Future of Loudspeakers will con vene on different dates in 2012 It begins on the last day of the CES in Las Vegas The symposium lasts two days Friday January 13 and Saturday January 14 It will also be held in a new location The Riviera Hotel The Symposium which is the largest event held in the world entirely dedicated to the loudspeaker industry will feature training courses covering various aspects of loudspeaker mod eling test and measurement and manufacturing In addition there will be technical paper presentations tutorial sessions round table and panel discussions an exhibit hall showcasing suppliers to the industry and plentiful networking opportuni ties Dr Floyd Toole will present a full day training session Loudspeakers and Rooms Designing Listening Experiences based on his recently published book Sound Reproduction This session explores loudspeaker and in room measurements and their interpretation in terms of listener perception There are many opportunities for animated discussion which the presenter welcomes Half day trainings will feature Active Noise Cancellation Special Considerations for Loudspeakers and Microphones by Mike Klasc
31. and mute the subwoofer The subs are powered by Class D amps with switching mode power supply They also feature extended excursion drivers with vented pole pieces to increase power handling and deliver long term reliability the company said Velodynes digital distortion limiting system enables the subwoofers to achieve maximum output without a risk of overdriving thus yielding deeper bass extension and less distortion the company added Down firing ports are designed to reduce audible port noise Savant Submits New Products at Expo Savant the supplier of home and commercial control and multi room A V systems is entering new product segments at the CEDIA Expo including architectural speakers The custom speakers designed by Bay Audio consist of four in wall models four in ceiling models an in wall subwoofer and related mounting accessories With the launch the company will offer a complete multi room audio solution consisting of speakers a multi room audio controller processor and a 16 channel amplifier which was introduced earlier this year KEF Offers High End Speakers KEF launched a new series of in room speakers at CEDIA Expo that will fit between the company s Q series and Reference series in price but come much closer to Reference performance than any previous series that was available at roughly the same price range Nine R series models available in October consist of three floor stand ing speakers two bookshelf spe
32. ate extended low frequencies thanks to reduced mechanical distortion which is usually generated by the woofer suspensions and reduced electrical distortion which is usually generated by a moving voice coil the company said In other planned launches the company updated its 150 THX Ultra2 certified speaker and S 1501 THX Ultra2 certified Mk 2 Tripole surround speaker Both add proprietary Pro high frequency tweeter with coated silk dome lightweight copper clad aluminum wire and waveguide to step up high frequency clarity and resolution The revised S 150T THX Ultra2 Tripole is a monopole dipole speaker suited for left right and back surround channels with 3 25 polypropylene cone driver on each side which generates the dipolar sound field and a direct radiating woofer tweeter combo on the front The driver complement generates solid imaging while also delivering diffuse ambience as needed As a result consumers dont have to make a choice between monopole and dipole speakers VC Using Your Digital Issue Previous page A Grab the corner to flip the page manually es o be on e gt is ARA A Ao Next page oo oo oo fs ls m e a E ee ee PS PE bL a T eish d es boke mi m emi ia ie h lt a e e e i e i e JE e ri pro e yee e p e e o e a o e y ae A A A A cl e a MA m E TORPEDO Be sure to check for rollover hotspot buttons which allow you to jump to a page or URL Navigation buttons
33. auto fuse holder amp blocks cable 8 wires amp kits installation accessory Hi Fi speaker parts and car audio components After the rapid development over the past years it covers 16400 square meters 300 employees and the new researching and developing center We are constantly offering high quality products with reasonable price and excellent service to customers from American European Asian countries and so on Warmly welcome to any of your inquiry and sincerely hope to establish good relationship with our customers from home and abroad Ningbo Yinzhou Huada Equipment Factory Add Jishigang Industrial Garden West suburb Ningbo City Zhejiang 315171 China Tel 86 574 88422259 884724559 88421258 Fax 86 574 88020128 89423885 Email huada mail nbpttzj cn Kathy huadasound com MY voice co Figure 3 and Figure 4 show different views domains of the same measurement for the individual passbands If we look at the group delay of this same data we can derive some valuable information The high frequency limit pla teau of each curve indicates the arrival time of the signal from that device From this we see that the cluster arrival time is approximately 3 3 ms This correlates very well with the ETC in Figure 4 Dont let the appearance of the subwoofer curve in the high frequency region be bothersome This is due to the low signal to noise ratio of the measurement above 400 Hz Referring to Figu
34. bs For more information visit www linearx com VC Figure 2 LinearX LF280 80 kHz 8 order passive low pass filter graph Photo 1 The Linear X LF280 Precision Amplifier Filter t Attenuator NEW voice com Ultra low distortion Coaxial Triaxtal point sources The advanced triaxial design aligns the acoustical centers of the transducers to produce a single point source This unique loudspeaker technology provides a coherent wave front without hot spots Precise directivity ensures uniform coverage with perfect time alignment between the components Innovative driver solutions European finest quality drivers for professional and high end loudspeaker applications Worldwide largest manufacturer of premium compression drivers Annular diaphragm Planar wave drivers cone drivers compression drivers compression drivers for line arrays EUROPEAN HIGH QUALITY SPEAKERS BMS Speakers GmbH Hannover Germany www bmsspeakers com MY Spotlight Subwoofer Alignment with Full Range System By Charlie Hughes have heard the following question asked many times How do I align a subwoofer with a full range loud speaker system I thought it might be interesting to delve into this to see if I could come up with an answer The task of adding a subwoofer to a loudspeaker system to increase the low frequency bandwidth should typically entail three primary items e The relative bandwidth of the subwoofer and the full
35. cay 20 VOICE COIL Photo 1 The SB26STAC C000 4 a 1 soft dome tweeter Impedance vs Freq w kr a o evo N SPL vs Freq HH HHH ER EII SN er N KN bh K EH l FEE HHHH mH b kkk NE e E E E a EEE ee E EERE l HHH HHA Figure 3 SB Acoustics SB26STAC C000 4 horizontal on and off axis frequency 0 solid 15 dot 30 dash 45 dash dot O A 0 L co L gt O Z a a a ms mn mn mu 7 273 Ta N m ao 5 t 2 y E E E E ma 5 5 6 p 2 T Et I C 5 ig A BU a E a r E AS a a a a 0 a a CJ Figure 5 SB Acoustics SB26STAC C000 4 two sample SPL Figure 7 SB Acoustics SB26STAC C000 4 Sound Check STFT eje a o 8 N 5 2 S E o a oe o 5 N n 2 al ra a d il 2 2 m q m T E 6 a S 2 1 LL ell Ea st l E o a we ee 20 H D N A F lt Es i i 3 Sl l N o N 2 S qa 4 ag e gt e un A y 9 a 5 O lt ij aq E 25 o l o x N o a E ps
36. classify or rate these distortions according to a number of well defined percep tual attributes and scales The software automatically adjusts the difficulty of each training task based on the listener s e Band Identification peaks dips peaks and dips low and high pass filters see Figure 1 e Attribute task bright dull full thin coloration reverberation noisy noise free hum hum free e Proven PureSound technology For the most reliable detection of different defect types Supports defects testing across all installed analyzer FX100 Audio Analyzer offers proven Pu reSou nd spea ker testing tech nology o Modular Analyzer eee Customize your speaker test system by choosing the number of analysis channels built in impedance and DC I resistance measurements switchers etc a LT e Cost efficiency System costs are controlled with modular configurations matched to specific applications e Maximum test speed Very fast glide sweep technology measures all quality para meters from a single Si FRA fraction ofa second e FX Control software sf orts Powerful and complete system control suite supp q i flexible GUI designs built in limits handling and sequenced pl measurements mi 8 1 Passed TE Er aE FLEXUS FX100 AUDIO ANALYZER NTi Audio AG Liechtenstein 423 239 6060 NEW voice com NTI Americas Inc Portland Oregon USA 1 503 684 7050
37. d be aware concerning microphone placement that could lead to mea sured differences That is the potential change in path length from the two devices under test lower freguency device and higher frequency device to the measurement microphone or the listeners ear At one mic position there may be very good summation At another location where the path length difference has changed by one half wavelength of frequencies in the crossover region there will be a notch cancellation in the summed response When making field measurements it is advisable to place the microphone s in position s that are typical of magnitude and arrival time differences to which most of the intended coverage area will be subjected Let s imagine a hypothetical system that has a full range cluster that reproduces 60 Hz to 14 kHz adequately We will NOVEMBER 2011 9 add a subwoofer that is physically displaced from the full Solen Fast Capacitors amp Solen Perfect Layer o range cluster The subwoofer reproduces adequately down Inductors often imitated sometimes copied to 30 Hz These response curves are shown in Figure 1 We even counterfeited yet never equaled want a crossover at 100 Hz with a 4 order Linkwitz Riley alignment Ne can simply apply a 4 Linkwitz Riley low pass filter at 100 Hz to the subwoofer since its response is relatively S O L E N flat well above the intended crossover region This is not the fo case fo
38. ding THXR VDC has the solutions O C D 7 C O O C O O X O O O gt Figure 13 Cone excursion curves for the 14 13 5 V curves in Figure 11 Tel 503 557 0427 vdc northwest com 2 ART v SCIENCE v TECHNOLOGY v DESIGN NOVEMBER 2011 FE Novembers Audio 2011 LIS ee wes on all Audio Amateur books N back issues archive CDs and sourcebooks With the information contained in these tools you can build the speaker of your dreams revamp your amps find reliable manufacturers and so much more Save big by buying annual magazine collections in bulk Elevate your audio know how with these incredible resource tools today Shop now at www CC Webshop com Coupon Code AUDIO112011 Offer Expires November 30 2011 AN INTERVIEW WITH ED DELL PAGE 17 OCTOBER 20 151 Til ry D A li aj G tat E JUDE SQId ole ies A Ls eo A A L oudspeaker lechnolo ay JBLS PROFESSIONAL STUDIO MONITOR DO S AND DON TS OF GRO November 2010 SPECIAL REPORT Twilight of the Rising Sun ter lech IOVAT 201 1 LI D offer inside includes LOC Design Suite software a 99 value VIS AR aem e om i MEET MR SROSEGTER sa esign 4 nidire ookbook E EAL poll JF P Fi A EE 1 E cr i 40 AX Digital pages ir i i J pS A men edition a erything you Need
39. ding professional association experience e A proven track record in successfully dealing with complex issues and relationships including leadership styles that successfully meet diverse situations e The vision to anticipate the future needs of the AES and the ability to recommend and initiate productive actions to meet those needs including organizational change e A bachelor s degree or higher from an accredited institution preferably in engineering or a related field e A commitment to preserving and enhancing AES s technical base further possessing a high level of comfort with both existing and emerging audio related technology as well as the ability to work with volunteers and staff to meet the technological needs of AESs membership e The stature to assume a leadership role in the professional engineering community i e with other professional technical societies the National Academy of Engineering the National Science Foundation the Acoustical Society of America the Institute of Electrical and the Electronic Engineers etc and their international counterparts e A commitment to preserve the collegial nature of a volunteer professional society that continues to take pride in operating as a volunteer staff patnership e The ability to recruit and empower capable staff to work productively with the volunteers to meet the goals and objectives of AES e Well developed communication skills and the
40. does not require the inclusion of any virtual sur round technologies or embedded surround sound decoding he added Reference dB levels are optimized for rooms with a volume of less than 2 000 ft whereas the HTIB standard is designed for rooms of 2 000 ft with sound pressure levels of 85 dB with 20 dB of headroom at a viewing distance of 10 The first soundbar meeting the standards is an active model from direct to consumer speaker supplier Teufel which sell only in the European Union That model on display at CEDIA Expo is an active 2 1 system with 350 W output separate subwoofer and analog and digital inputs Velodyne Reduces Initial Price Point Velodyne reduced its opening price point on active sub woofers with room correction technology to 479 with the launch here of four models in the EQ MAX series The series consists of 8 10 12 and 15 models at respective retail prices of 479 579 679 and 979 All come with remote control of subwoofer functions including room correction To use the subs five band DSP based room correction tech nology users place a subwoofer in its intended location place the included microphone in the desired listening location and push the remote control s EQ button the company said In addition to controlling the EQ function the subs remote lets users adjust phase switch among presets set the sub to night mode to limit output illuminate the subs front display
41. e a strong imaging throughout a room regardless of speaker placement the company said The brand first floor standing speaker the 9505 is a floor standing version of the 950 monitor which launched last year to fit between the 750 THX Select speaker and the 150 THX Ultra speaker The sealed enclosure 950F is 48 tall but nar row to provide a minimal footprint It is said to deliver a wide sweet spot Designed for use with any MK Sound subwoofer the 950F features dual 5 25 polypropylene woofers MK s Sound Pro tweeter and the company s Phase Focused crossover which optimizes response in both the vertical and horizontal planes The open back tweeter is said to be fast and accurate while eliminating high frequency smearing and phase combing anomalies It sports a metal mesh curved grille that is acousti cally inert and held in place with magnets to eliminate the buzzing and rattling For its MP7 on wall speaker the company developed a reduced depth version of its in room M7 but retained the M7 s internal volume to retain the audio quality of a full size compact speaker the company said Its designed for use with flat screen TVs In powered subs the company unveiled the X8 X10 and X12 subwoofers which feature two 8 two 10 and two 12 drivers respectively In each sub the drivers are arrayed in a push pull configuration with front mounted woofer and identical bottom mounted back out woofer to deliver high SPLs and accur
42. e have seen how the response of an electrical filter can combine with the response of a loudspeaker to yield the desired response alignment from the combined output We have seen how the low pass behavior of a device may make it appear that its arrival time is later than it actually is We also demon strated how to use group delay to determine the correct delay setting with relatively high precision when the high frequency output of a device is limited due to its low pass behavior I hope that some will find use for these techniques VE high temperature edge wound and multiple layer flat wound coils for the pro audio home theater and automotive aftermarket onest guay Come sie OF IMpOTIed cors Figure 11 IR of low pass filter with different corner frequencies Custom coils available in e Multi layer wire configurations e Free standing coils e Multiple lead configurations e Multiple wire types e Round and Flat Wire e Bifilar or Edgewound i e Custom lead out attachments e Custom bobbin wound coils i High temperature adhesive coated Copper and Aluminum wire in round and flat sizes CCAW wire available in round sizes Adhesive coated custom cut forms and Collars Custom slit rolls of Form and Collar material available coated or uncoated RENEW your Su bscri ption nan l iP to VOICE COIL Precision Econowind Inc SA ad 8940 North Fork Drive North
43. e response with maximum passband flatness A common problem with any passive filter is loading by the external cable capacitance or analyzer meter input circuitry which can alter the response The LF280 provides a precision R2R ladder attenuator which largely removes the effects of external device loading and provides a constant low output impedance regardless of the attenuation selected For attenua tion levels of 6 dB 12 dB or lower the effects of any exter nal device loading are effectively eliminated An additional advantage of the precision attenuator is to reduce signal levels fed to other measuring devices which may not be capable of handling the very large signals produced from high power amplifiers Features include Dual precision passive 8 order 80 kHz low pass filters e Dual precision 30 dB attenuators with 6 dB steps e Dual channel single ended or mono bridged differential mode e High power capability 90 VRMS channel or 180 VRMS bridged e Very flat passband response 0 05 dB to 30 kHz e Very high stopband response gt 60 dB above 200 kHz e Very high linearity at high signal levels e Low sensitivity to cable analyzer loading e Constant output impedance 330 Q Ch e Dual five way binding post amplifier connectors e Dual BNC and XLR output signal connectors e Short circuit output protection e Efficient high performance low cost design e Small size 1 8 x 4 0 x 7 0 46 x 101 x 178 mm 2 l
44. efore your 21 TEST BENCH 4 SB Acoustics and Parts Express Home Audio Applications B By Vance Dickason 2 ee li Spotlight A Message from Ed Dell mula ec mateur Inc is in a wonderful transit Will have been acquired by the Eleki read this The Elektor group publi marine and the North American vers ES a more firm well fund Check your label to find the expiration date es The buyers h ve major plans tos For more information call 860 875 2199 x206 d audioN press Voice Coil our two er ndustrv Sourcebook und The Wo and our list of books and CDs sonal note some of you know that bai in 1970 pnd that we m our 4 ve hon Birthdays pile up February will be 89 am in fine hes is in time to hand the reins to othe Qualified subscriptions to Voice Coil run for one year er for a long ume and my dove for thi s mdimmsbed aim deeply pleased A PA PP PL Pe P P L Pei PP Peri PP Manana la I dl ll ily l lll sink I hills UH Ferna UT iki amor Dr kaisan 4 Park street 4 Park sir Vernon OT h i VOICE fl COIL Renew annually online at WWW voiceccollma faz TATANEN Aiii a ae a lt 0 Industry Watch By Vance Dickason Economy Impacts CEDIA Expo Attendance Attendance at CEDIA Expo 2011 in Indianapolis dropped 14 9 from last years Expo to approximately 17 600 according to a press release issued by CEDIA Of the 17 600 who attended 25
45. entation Sourcing Guidance sponsors of The Loudspeaker University seminars MENLO SCIENTIFIC USA tel 510 758 9014 Michael Klasco info0menloscientific com www menloscientific com cluster This yields the summation along with the individual passbands shown in Figure 8 and Figure 9 This is almost the Ee a oe T E slope storie exact response we desire There is less than 0 5 dB error in the l mm kilelen vicinity of 150 Hz This error is due to the output of the cluster and high pass filter not exactly matching the Linkwitz Riley target see Figure 2 There is one more item that think might be of interest in helping to see how a low pass filter response affects apparent arrival time say apparent because it only appears that the arrival time is changing Figure 10 and Figure 11 show the ETC and IR respectively of a 4 order Butterworth low pass filter The only difference in these curves is the corner fre quency 3 dB point of the filter The true arrival time for all of these filter curves is 5 ms A complementary high pass filter Figure 9 ETC of individual passbands and the summed response with the cluster delayed 7 1 ms with an arrival time of 5 ms will combine properly with its low pass counterpart in the graph If the high pass is delayed so as to place the arrival so that it occurs later than 5 ms there will be errors in the summation of the filters just as was illustrated in Figure 5 and Figure 6 W
46. equired for AES to refine and suc cessfully meet its strategic objectives and successfully conduct operations in accordance with its educational and scientific purpose The headquarters office of the AES is in New York City N Y Publisher Hugo Van haecke Editor Vance Dickason E mail vdc northwest com COIL Editorial Coordinator Editorial Assistant Shannon Barraclough Marketing Director KC Prescott Graphics Jeff Yanco Controller Debbie Lavoie Customer Service Valerie Luster Administrative Coordinator FAX 860 871 0411 Periodical rates paid at Vernon CT and additional offices Copyright 2011 by Segment LLC All rights reserved Quotation from Voice Coil is forbidden without written permission of Submissions Send all press releases and information to Voice Coil Segment LLC Editorial Dept 4 Park St Vernon CT 06066 or FAX us material at 860 871 0411 or e mail editorial audioXpress com the publisher NU voice com tion which conflicts with this obligation without prior specific written consent of the Board of Governors Qualifications for Executive Director Applicants e Previous successful executive leadership experience in diverse and decentralized global not for profit associations e Strong but flexible knowledge based leadership qualities and the ability to operate in a constantly changing environment e Sufficient high level management experience preferably inclu
47. g response to above 40 kHz Small size 65 mm OD available without face plate WWW Wavecor com GREY voice com Figure 2a The tube is itself the total volume of the enclosure in which the driver is mounted b The bellows based tube is attached to an enclosure volume as an additional element acoustic suspension type system that includes an enclosure wall that is flexible Nowhere is it stated that the system operates a bass reflex Helmholtz resonator or that the flexible bellows and mass are effectively a form of a passive radiator On the other hand the illustrations show and the specification describes small holes that are to be placed in the walls of the corrugated bellows and are said to be there for the purpose of changing the compliance of the side walls of the bellows In general the discussion of the technology appears to mirror some of the old loudspeakers of decades ago that introduced flexing walls to release more energy or reduce the acoustic stiff ness of the air volume of the sealed enclosure One wonders if a more in depth analysis modeling and optimization of the architecture would possibly reveal any particular advantages over conventional systems In general flexing walls will create a loss reducing the Q of the Helmholtz resonant output It is possible that some variation on this form could provide a smaller passive radiator with a great excursion capability but it would seem that this w
48. inter national organization with the purpose of uniting persons per forming professional services in the audio engineering field and its allied arts collecting collating and disseminating scientific knowledge in the field of audio engineering and its allied arts advancing such science in both theoretical and practical appli cations and preparing publishing and distributing literature and periodicals relative to the foregoing purposes and policies Currently over 14 000 members are affiliated with more than 75 AES professional sections and more than 95 AFS stu dent sections around the world The AFS also serves the edu cational needs of its members and the audio industry at large through international technical meetings equipment exhibi tions and a wide range of publications Conventions which include scientific presentations student activities workshops and exhibitions are held annually both in the United States and Europe Additional conferences and regional summits are held periodically throughout Latin America Asia Europe and North America Capsule Job Description of the Executive Director The executive director ED facilitates the operational activi ties of the AES and serves as the Societys chief operating officer The ED is responsible to the AES Board of Governors and its Executive Committee which provide overall policy guidance and operational oversight The ED provides leadership and performs such duties as r
49. k to get a 2 83 V 1 m impulse response for this driver and imported the data into Listen Inc s SoundMap Time Frequency software The resulting CSD waterfall plot is given in Figure 23 and the Wigner Ville for its better low frequency performance plot in Figure 24 All things taken together and since I know that Frank and Ulrik Danesian Audio spend a lot of time listening to vari ous iterations of a driver as they go through the development process I m guessing that this is a very fine sounding product For more information on the SB26STAC and MWI16R Satori woofer and other SB Acoustics drivers visit the SB Acoustics 3 Figure 24 SB Acoustics MW16R SoundCheck Wigner Ville plot website at www sbacoustics com VC MES voice com HiVi Inc California 11630 Goldring Road Arcadia CA 91006 Tel 1 626 930 0606 Fax 1 626 930 0609 HiVi RESEARCH China Jiangjun Industrial Zone Nantou Town Zhongshan City Guangdong China Tel 86 60 23112898 Fax 86 760 23380899 E mail sales zs hivi com global hivi com www hivi com Alvi and the Swans logo are registered trademark of HIVI inc Or its subsidiaries in the United State and other countries All rights reserved LUME Z4 e e E VOIC THE PERIODICAL Fea IN Si INDUSTRY NEWS AND DEVELOPME 10 a INDUSTRY WATC Sy Vance Oickason 12 W SPOTLIGHT Ae age from Ed Dell your Subscription a 18 A ACOUSTIC PATEN Dr James Croft to Voice Coil b
50. nator product line and the Vifa NE series This frame has its own unique features but like the Scan and Vifa woofers the frame has a minimal reflective footprint behind the cone to cause reflections and a completely open area beneath the spider mounting shelf Both are highly desir able attributes The spider mounting shelf itself is pinned o to the frame to limit vibration transfer from the frame to this part of the suspension system The neodymium motor cup attaches to the bottom of the frame and has a separate cosmetic heatsink part that looks like the continuation of the frame attached to the peripheral of the motor The motor is comprised of neodymium ring magnet and e the cup that completes the field and forms the gap area In addition see the FEA motor cutaway in Figure 9 there is an overhung copper sleeve shorting ring to reduce distortion The device uses a 1 4 36 mm diameter voice coil with a Kapton former wound with round copper wire and termi nated to a pair of gold plated terminals The cone and dust cap material are also very unique and composed of 60 pure Egyptian papyrus parchment fibers a very expensive but light and stiff material This incidentally e is available in the black cone seen in the accompanying photo as well as a natural off white color if you are going for that Yamaha NS 10 look Suspension is provided by a NBR sur round that uses a special vertical and ho
51. nspectors subject every item to an intensive OC procedure including materials inspection as well as granularity pressure and sintering temperature tests We have also been a Sony Green Partner since 2006 and are ISO 14001 2004 certified proving our commitment to the strictest of environmental standards Our magnets are mainly used for speakers wind power generating devices motors electronics auto parts and more Every month we manufacture up to 1 200 tons of ferrite magnets 150 tons of neodymium magnets and 30 tons of alnico magnets All of our items are RoHS marked for easy distribution in eco conscious markets For more information inquire today b one mag iamen One Magnet Electronic Co Ltd Headquarters 9 F Lixin Plaza 90 South Hubin Rd Xiamen Fujian 361004 Ghina Tel 86 592 239 7378 7379 Fax 86 592 239 7381 6476 Factory Shitou Industrial Zone Lujiang Anhui China Tel 86 565 793 7721 7722 Fax 86 565 793 7728 E mail onemagnet one magnet com onemagnet globalsources com www one magnet com www globalsources com onemagnet co Global Sources Verified Supplier xx Our selection includes Neodymium magnets Ferrite magnets Alnico magnets 150 9001 2000 150 14001 2004 ISO TS 16949 2002 NOVEMBER 2011 substantially constant ratio of wavelength vs source size over a wide range of frequencies s one can see even with its high value simplicity this appr
52. o of Menlo Scientific and Cone Vibration and Sound Radiation by Dr Wolfgang Klippel This years panel discussion topic will be Neodymium Coping with the Consequences of Supply and Demand Elasticity International will continue this discussion begun at the Panel chairman Spiro Iraclianos of Harman International AES The use of neodymium iron boron mag nets has been increasing over the last few decades to address In a system where balance is key you could easily prefer these over any other cable out there whatever the cost Alan Sircom Editor June 2011 audience av com 760 471 0202 the demands of compact high energy motor applications Loudspeakers have been adapting the super magnets to deli cately balance the size performance ratio demands in today s marketplace In recent months the availability of neodymium has been shrinking while the cost of the magnets which use 5 the rare earth element has skyrocketed The workshop will serve as a forum for industry professionals from all aspects of the value chain to collectively discuss and begin to address the facts and myths surrounding the global issue which has caused significant paradigm shifts in the way we think about the future of the industry The ALMA Winter Symposium will overlap and parallel the International Conference on Consumer Electronics ICCE presented by the IEEE Consumer Electronics Society
53. oach is not as common as the alterna tives because its usability is at the effect of the problems of series connected drivers and associated impedance liabilities But if the conditions are suitable it is a most efficient way to crossover and level shift multiple similar drivers in an effective manner ELASTOMER LOUDSPEAKER BOX SYSTEM Publication Number U S 2011 0216933 Inventors Quiling Lan Guangki CN Assignee None disclosed Filed November 28 2008 Published September 8 2011 U S Class 381 386 25 Drawings 10 Claims REVIEWER COMMENTS Now this is a curious speaker enclosure concept Whether it actually has utility or not is yet to be determined The device has two basic forms see Figure 2a and Figure 2b The novel portion is that of a cylindrical tube that is formed from a type of multi pleated bellows with a circular plate mounted at one end that both seals off the tube and also has the characteristic of acoustic mass In the Figure 2a example the tube is itself the total volume of the enclosure in which the driver is mounted In the Figure 2b example the bellows based tube is attached to an enclosure volume as an additional element The inventors view of his invention is that it is a sealed box wavVecor Innovative 22 mm dome tweeter Powerful outer neodymium ring magnet Large center hole for effective venting Reflection free rear chamber Resonance frequency 800 Hz Textile dome yieldin
54. of Af will yield low time resolution large values of At We need higher frequency output from the subwoofer correspond ing to higher Af lower frequency resolution to increase the time resolution in order for us to know when to position the cluster If possible we can bypass the low pass filter on the subwoofer to get more high frequency content in the output signal This may help in more precisely determining the arrival time of energy from the subwoofer Let s assume that we cant do this or if we can that it still doesnt give us sufficient time resolution What we need is a way to get precise time information without high frequency content This is a seemingly impos sible task but only so in the time domain In the frequency domain there is a metric available that yields quite precise relative timing information This is the group delay The group delay is defined mathematically as the negative rate of change of the phase response with respect to frequency d SS Ki Figure 5 Magnitude response summed response with the cluster delayed 10 ms red and 14 7 ms blue Fi ol i ees in zer TTE ar a a E Figure 6 ETC of the summed response with the cluster delayed 10 ms red and 14 7 ms blue LAA pee AE eae T structure ir n o A A ee a a gt sa d pistig ey iU NOVEMBER 2011 HN established in 1993 is a leading manufacturer and Huada Ningbo Yinzhou Huada Sound Equipment Factory supplier of
55. ould be plagued with possible extraneous mechanical noise generation during large excursions and also the required mass for low frequency tuning would most likely cause the device to sag with the bellows loosing its ability to fully support the weight required for the system to be tuned to a low frequency From the reading of the patent I dont expect any breakthroughs in performance but it is always possible that a review of this type of inventor s effort just might stimulate new thoughts allowing the creation of new useful ideas by others ULTRA LOW FREQUENCY TRANSDUCER AND LOUD SPEAKER COMPRISING SAME Patent Number U S 8 023 688 Inventors Steven M Irby Stillwater OK William O Doerring Figure 3a The enclosure has a square opening to mount the transducer b The transducer diaphragm suspension and frame have a square periphery We Offer Ribbon ESS 3 eee Gl Ribbon Speaker Is om SSS 4 e BESTON Technology Corporation Address 5F 13 No 9 Ai Kuo West Rd Taipei 100 Taiwan TEL 886 2 23892956 FAX 886 2 23892952 E Mail s272 ms45 hinet net Stillwater OK Assignee Stillwater Designs and Audio Inc Stillwater OK Filed January 29 2008 Granted September 20 2011 Current Class 381 398 11 Claims 4 Drawings Reviewer Comments Disclosed is a loudspeaker system including a transducer with the transducer assembly supported inside an enclosure In this loudspeaker the enclos
56. r the cluster however Its output is already beginning to decrease with decreasing frequency through the intended crossover region We will need to apply an electrical filter that when combined with the natural response of the clus ter will yield an acoustical output that matches a 4 order Linkwitz Riley filter with an Fc of 100 Hz Figure 2 shows p ili Bekka happa ANA A Ni A A A AA vee A gt mmm a x m a amm Em n a Figure 3 Magnitude response of individual passbands and the summed response m cs RI Milan sz EA ee SOLEN CAPACITORS Metallized Polypropylene Film Fast Capacitors First to use the Fast Capacitor winding technique First to use bi axially oriented metallized polypropylene film Lowest dissipation factor lowest dielectric absorption Widest range of values from 0 01 pF to 330 uF Wide range of voltages from 250 Vde to 630 Vde Metallized Teflon Film 27 pF 10 pF 1000Vde Teflon Film amp Tin Foil 033 uF 62 uF 450 Vde 1000 Vdc Polypropylene Film amp Tin Foil 01 pF 4 7 pF 100 Vde 630 Vdc Metallized Polyester Film 1 0 pF 47 uF 160 Vde Non Polar Electrolytic 5 DF 10 pF 330 pF 100 Vac o Figure 4 ETC of individual passbands SOLEN INDUCTORS Perfect Layer Hexagonal Winding Air Core 2 First to use Perfect Layer Hexagonal winding
57. re 3 the output of the subwoofer is less than 24 dB at 200 Hz Our use of a 4 order filter would indicate a level of less than 48 dB at 400 Hz and decreasing rapidly It s no wonder there is an SNR problem at higher frequencies We can look at the subwoofer curve around 300 Hz to get an indication of the high frequency limit of its group delay This turns out to be approximately 11 0 ms The group delay of the cluster at this frequency is approximately 3 9 ms This is a bit different than the 3 3 ms at higher fre quencies This is caused by the phase shift of the high pass filter and the natural high pass response of the device The low pass filter being used on the subwoofer will have similar phase shift and consequently similar group delay differ ences in the high frequency region if our measurement SNR was good enough to see it Taking the difference in 11 0 ms and 3 9 ms we now have a value of 7 1 ms to use as our delay setting for the Em Figure 7 Group delay of the cluster red and subwoofer blue with crossover filters in place e PA E E Eg E Figure 8 Magnitude response of individual passbands and the summed response with the cluster delayed 7 1 ms Engineering Consulting for the Audio Community Liaison Between Materials suppliers 4 Audio Manufacturers Technical Support for Headset Mic Speaker 4 Manufacturers Product Development Test 4 Measurement Instrum
58. rizontal attachment process along with a Dr Kurt Muller Bimax spider Bimax is purported to have less twisting tendencies compared to other cloth spider materials and is warm shaped with a durometer resin added mass measurement and instead used actual measured mass but the manufacturers measured Mmd data At this point the 10 V curves were discarded as being too nonlinear ZA voice com waterfall plot given in I commenced analysis of the MW16R using the LinearX LMS analyzer soon to be replaced by a more advanced outboard chassis with USB interface analzyer called the LX500 and VIBox to create both voltage and admittance current curves with the driver clamped to a rigid test fixture in free air at 0 3 V 1 V 3 V 6 V and 10 V As has become the protocol for Test Bench testing I no longer use a single for the curve fitting algorithm to resolve Next the remaining eight 550 point stepped sine wave sweeps for each MW16R sample were post processed and the voltage curves divided by the current curves admittance curves to derive imped ance curves phase added by the LMS calculation method and along with the accompanying voltage curves imported to the LEAP 5 Enclosure Shop software Since most Thiele Small data provided by the majority of OEM manufacturers is generated using either the standard model or the LEAP 4 TSL model I additionally created a LEAP 4 TSL parameter set using the 1
59. ud speaker market including transducers for home audio car audio pro sound multi media or musical instrument applications While many of the drivers featured in Voice Coil come from OEM that have a stable catalog of product this is not a necessary criterion for submission Any woofer midrange or tweeter an OEM manufacture feels is repre sentative of their work is welcome to send samples Please contact Voice Coil Editor Vance Dickason prior to submis sion to discuss which drivers are being submitted Samples should be sent in pairs and addressed to ZA voice com Vance Dickason Consulting 333 5 State St 152 Lake Oswego OR 97034 503 557 0427 vdc northwest com All samples must include any published data on the prod uct patent information or any special information necessary to explain the functioning of the transducer This should include details regarding the materials used to construct the transducer such as cone material voice coil former material and voice coil wire type For woofers and midrange drivers please include the voice coil height gap height RMS power handling and physically measured Mmd complete cone assembly including the cone surround spider and voice coil with 50 of the spider surround and leadwires removed Kms Symmetry Range curves for the SB Acoustics MW16R Impedance vs Freq The Kms X curve is very symmetrical in both directions but also with a small rearward coil in offset of
60. ure 1 U S Patent 8 005 240 one driver as a desired frequency is approached The result is an aesthetically pleasing speaker that has dual in plane drivers and that produces superior sound quality throughout the entire frequency range of the speaker including those ranges in which dual in plane drivers tend to acoustically interfere with each other A frequency dependent shunting network such as a low pass filter is applied to one of the drivers so as to gradually mute the INDEPENDENT CLAIMS 1 A speaker operably secured to a network for applying an appropriate frequency component of an electrical input drive signal said speaker comprising a frame a pair of drivers oper ably secured to said frame and spaced apart from each other by a defined distance said pair of drivers mounted substantially in the same plane and connected in series to the network said pair of drivers configured to operate within substantially the same range of frequencies and a capacitor operably secured to one Measurement Mic system 7052E Titanlum Diaphragm Now 4 Hz to gt 25 kHz lt 20 dBA gt 140 dBSPL MK224 Optional 4048 Preamp 2 uV A gt 5 Vrms 4 Hz gt 100 kHz 18 to 60 Vac driver of said pair of drivers so as to gradually mute said one driv er as a predefined frequency is approached and a capacitance of the capacitor to gradually mute said one driver at the predefined frequency is a function of the defined distance 11 A
61. ure has a square opening to mount the transducer The transducer diaphragm suspension and frame have a square periphery shaped to conform to the opening in the enclosure for the purpose of maximizing the diaphragm surface area for a given square face of the enclosure The low frequency transducer is optimized to be utilized as a subwoofer for automotive speaker systems operating over an approximate range of 20 Hz to 80 Hz The substantially square and concave diaphragm includes a convex surround around the periphery of the diaphragm with pleated corners to minimize binding of the suspension corners during large excursions For increased durability under high force conditions trusses are formed in the diaphragm The invention is basically a claim that the specific combina tion of attributes of the well designed rugged high output sub woofers for use in automobiles as one can find in the Stillwater Kicker series models going back to 1999 and including the current SoloX and Solo Baric L7 all of which have stood the test of time as competitive devices VC PROFESSIONAL LOUDSPEAKERS 18x _1600 MORE THAN JUST AN EIGHTEEN MORE POWER 3200 W Maximum Power MORE EXCURSION 28 mm 56 mm MORE LINEARITY Exceptional DC Offset Control MORE VERSATILE 12 2 Kg 26 9 Ib Pure Bass Reflex Application WANT MORE INFO AND A FREE QUOTE WWW FAITALPRO COM SALES QUOTATION Li TI wi FalialFR n Tacelagili NOVEMBER 2
62. zer set to a 100 point gated sine wave sweep Figure 19 gives the Figure 11 SB Acoustics MW16R computer box simulations black Satori woofers on axis response indicating a smoothly rising solid sealed 2 83 V blue dash vented 2 83 V black solid 2 response to about 1 kHz then flattening out up to 3 kHz sealed 14 V blue dash vented 13 5 V l Loudspeaker Product Development Time vs Freq Vance Dickason Consulting has been developing award winning products for numerous high profile brand names for over 20 years experience that s hard to find Add to that an available design team that includes some of the best transducers engineers industrial designers and marketing experts I know of in the industry and you have a winning combination that would cost well over 750 000 a year to keep in house With extensive experience in high end off wall in wall on wall ceiling and subwoofer products plus close relationships with some of the worlds best speaker OEM s and you have a combination of services that will accelerate your next product lineup We have all the best toys Klippel LEAP 5 amp LMS CLIO MLSSA LSPCad FEA so whether its multimedia car audio MI Pro two channel or Home Theater inclu

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