DOCSLIB.ORG

Ready for Digital Audio?

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ready for Digital Audio? Technology Update Readyfor digitalaudio? It mightarrive sooner than you think Andy Rappaport, AssociateEditor By the end of this year, you might be buying hourJong stereo records that fit in your pocket. Not only will these disks be small, but their manufacturers claim they will offer lower distortion, wider dynamic range and flatter frequency re- sponsethan conventionalLPs. You won't be able to play the records on your present turntable, though-these first commercial products of the digital-audio revolu- tion will have no grooves and will spin much faster than 33/s rpm. Although the digital-audio tech- nology behind such devices isn't new, the high cost and complexity of the required conversionand storage have confined its application pri- Onfy 4.7 in. across, the Sony Compact Disk (CD) holds as much as t hr of digital stereo marily to professional equipment. audio. CD players should be available in the US by the end of this year. Now, however, as data converters' prices drop as fast as their exists, but record companieswill be end of this year, is basedon a 4.7-in. accuraciesimprove and as practical reluctant to invest in expensive (12-cm) optically encoded disk. high-density storage media become digital-disk or tape-production facil- Similar to the larger Sony video- available, you'll see a proliferation ities that they feel might become disk, the CD record contains a of low-cost consumer-orienteddigi- obsolete.Furthermore, operatorsof 2.5-milong helical track of 0.6-pm- tal-audio products. The develop- recording studios, where audio wide pits and flats spaced1.2 pm ment of these deviceswill not only signalsare first digitizedand mixed, apart-allowing 8x10e active bits radically changethe audio industry, will delay spendingthe 9200,000to per record. As it's scanned,the disk but will also affect general data $300,000 to equip their setups alternately reflects and disperses a acquisition and signal processing. until a standard is developed. solid-state-laserbeam. To circumventthis problem,some The Sony/Philips system uses a Still no standards equipment manufacturers are en- 16-bit linear-encodedpulse-code- One of the biggest problems now tering cooperativeagreements with modulation (PCM) format with a confronting digital-audio-equipment record producers. The first such 44.3-kHzsampling rate. Sony claims designers is a lack of industry venture, between Sony (Tokyo) and the system achieves more than standardization. Committees in CBS/Japan (Tokyo), entails a joint 90-dB dlmamic range and channel Japan, Europe and the US are commitment to produce the Com- separation with less than 0.05Vo discussingthe subject, but none has pact Disk (CD) systemdeveloped by total harmonic distortion (THD). It yet made a satisfactory recommen- Sony and NV Philips (Eindhoven, compares these specs with the dation. Hardware manufacturers Netherlands). Both Sony and Phil- 35-dB channel separation, 55-dB expect that the first system to gain ips will manufacture players, and dynamic range and 0.2Vo THD widespread consumer acceptance CBS will releasea limited catalogof typical of an analog LP record (see will establish a de-facto standard- disks. The two equipment makers box, "Are digital specs as good as one the industry is forced to adopt. hope that availability of the CBS they look?"). This approach,however, results disks will establish the feasibility of The CD player eliminates wow in the classic chicken-or-egg prob- the CD system and that other rec- and flutter'by servoing the disk's lem: Manufacturers won't sell ord companieswill join the fold. speed to maintain a constant data enough machines for a standard to The CD system, which Sony rate. The player comparesincoming develop unless sufficient software expectsto releasein the US by the data with an internal crystal i EDN FEBRUARY3, 1982 6l Technology Update reference, and the resulting error digital-audio-disk player, capable of Philips, other Japanese companies signal controlstheunit's motor. The generating 5 hrs of programming on have developed digital-audio-disk optical bit length remains constant two sides. It feels that the smaller players. Of the 16 that demonstrat- throughout the record's.track; thus, system, which plays for t hr using ed machines at the recent Tokyo the player must maintain constant only one side, represents a better Audio Fair, most use the CD linear velocity by decreasing disk choice because it's cheaper and format. A few, however, are rotation speed.as the laser scans matches the analog LP's program- experimenting with systems of outward from the record's center. ming format. Moreover, the CD their own. system is small enough for use in JVC, for example, is working on Car CD system coming cars, and Sony promises an automo- an audio adapter, termed AHD, for Sony has stopped development of tive system soon. its VHD Series videodisk systems. its previously demonstrated 12-in. Not to be outdone by Sony and An AHDA/HD combination can Until digital audio takes over... Digitalaudio is coming,but don't throwaway your to produce.As a result,record companies will be slow presentgear -you'll have to convertit gradually. in issuingdigital disks, and these records initially will First,you'll need to investabout $800 to $1000in a be 50 to 100% more expensive. digital-audio-diskplayer. Manufacturershope that But while you'rewaiting for digitalaudio to take theseunits will become less expensive, although they over,you can benefitfrom analog-audio innovations. feelthat even the costlierearly units will be no more Twocompanies, for example,have introduced analog expensivethan analog turntablesof comparable signal-processingsystems that allowconventionally quality. manufacturedLPs to otfer-at lowercost-the same Second,you won't see too many digitalrecords dynamic range as the digital disks. Both firms' soon.Optical disks require totally ditferent manufac- techniquesinvolve compressing a signal'sdynamic turing processesthan analog LPs, so to produce range as a record is cut and then restoringthe them, recordcompanies will have to make large signal'soriginal characteristics during playback. In- investmentsin plantsand equipment.Furthermore, steadof requiringa completelynew player, listening the digitalrecords are similarto videodisks,which, to these recordsdemands only that you buy an althoughsimple in concept,have proven very difficult inexpensiveprocessor that connectsto yourcurrent RIGHT OUTPUT A 4-flfter array provides the time constanfs in CBS3 CX decoder. A deadband in the rectilier circuit prevents expansion of very-lowlevel signals. Encoders are formed by putting the decoder in an op amp's feedback loop. EDN FEBRUARY3. 1982 I Technology Update display still video pictures as well as Lake City, UT) has also proposed a 3x3-in. record to hold as much as 1 provide stereo audio. No marketing different type of digital-audio play- hr of stereo audio. Moreover, plans for the unit have yet been er. Its system employs a moving because high-resolution frlm proc- announced. optical scanner that reads a essing is a well-established art and Sources within the industry also stationary record. The fixed-record photographic materials are inexpen- expect RCA to introduce some t5pe design, the firm claims, results in a sive, a record for the firm's machine of audio device for its CED Series less complicated and potentially could be made for only $1. This low videodisk players, but no specifics cheaper system than the Japanese cost, coupled with simple process- are available. spinning-disk units. irg, should make the system Digital Recording says that its attractive to low-volume record Fixed record, moving reader unit packs as many as 3x 108bits/in.2 producers, according to the sys- Digital Recording Corp (Salt on silver-halide film, allowing a tem's designers. preampor recever. CBS licensesthe decodercircuitry to equipment The GX system, recently developedat CBS manufacturersfor a smallfeeand provides encoders TechnologyCenter (Stamford,CT), allows record to interestedrecord producers.A few companies companiesto makeanalog LPs from digitalmaster havealready signed licensing agreements, so CBS tapeswith no loss of dynamicrange. When played anticipatesthat CX decodersand recordswill soon througha CX decoder,the encodedrecords otfer a be available. 20-dBhigher signal-to-noise ratio than conventional Untilthe systemgains widespread acceptance, its LPs. In addition,CBS claimsmost listenersnotice developerspredict, some existingrecords will be onlya minorloss of soundquality when playing back reissuedin the CX format,and new releaseswill be .theCX diskswithout a decoder. availablein bothnormaland encoded form. Addition- The CX encodercompresses by 2:1 the dynamic ally someJapanese manufacturers have expressed rangeof all signalsexcept those more than 40 dB interestin incorporatingCX circuitryinto their receiv- below a referencelevel; the compressionslope ers,and to makethese plans economically feasible, convertsrapidly to 1:1 below -40 dB. CBS claims threesemiconductor houses are reportedworking on thatbyleaving very low signals unaltered, the system decoderlOs. preventsmaster-tape hiss from becoming louder than A second analog-disk-enhancementsystem, of- record-surfacenoise. fered by DBX Inc (Newton,MA), also employsa To minimizethe etfectsof CX compressionon compression/expansiontechnique. In this system, recordsplayed back withouta decoder,the encoder though,all signalsare compressed2:1 regardlessof maintainsflat frequency response. Besides providing level.Input signals are rms-detectedand processed
Load more

Recommended publications
  • PNWAS Audioletter May 2011
    May 2011 n a m t t i P e o J y b s o t o h p by Joe Pittman any members commented that club’s system) throughout the presenta- digital recorder changed the audiophile the April meeting was one of the tion (see play list). world. best meetings ever. We were fortunate Unfortunately, the presentation was The sample music was out- to have Jules Bloomenthal give us a so comprehensive, I can’t go over it all standing, with some of the members, slide-show presentation of the back- here (I was too busy listening and not immediately hunting for the recordings ground and history of the Soundstream taking notes anyway). But highlights on the internet after the meeting (a new digital recorder. He brought the original included the hard science involved with competitive event?) commercial unit (which he now owns) the original design by Dr. Thomas Jules mentioned that he’s writing a that was used to make the first re- Stockham, Jr., the early years of Sound- book about Soundstream. So I hope it cording (it was on static display) and he stream (1971-1979), the famous Telarc comes out some day, it would be a great played example recordings (on the recording of the 1812 Overture using read. Thanks Jules for the outstanding real canons, and how Soundstream’s presentation! Pacific Northwest Audio Society, P.O. Box 435, Mercer Island, WA 98040 ● www.audiosociety.org 2 first commercial digital recorder. cinating background and history ofJules the Bloomenthal creation kick’s of off the the meeting with the fas- Pacific Northwest Audio Society Audioletter May
    [Show full text]
  • Vinyl Theory
    Vinyl Theory Jeffrey R. Di Leo Copyright © 2020 by Jefrey R. Di Leo Lever Press (leverpress.org) is a publisher of pathbreaking scholarship. Supported by a consortium of liberal arts institutions focused on, and renowned for, excellence in both research and teaching, our press is grounded on three essential commitments: to publish rich media digital books simultaneously available in print, to be a peer-reviewed, open access press that charges no fees to either authors or their institutions, and to be a press aligned with the ethos and mission of liberal arts colleges. This work is licensed under the Creative Commons Attribution- NonCommercial 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA. The complete manuscript of this work was subjected to a partly closed (“single blind”) review process. For more information, please see our Peer Review Commitments and Guidelines at https://www.leverpress.org/peerreview DOI: https://doi.org/10.3998/mpub.11676127 Print ISBN: 978-1-64315-015-4 Open access ISBN: 978-1-64315-016-1 Library of Congress Control Number: 2019954611 Published in the United States of America by Lever Press, in partnership with Amherst College Press and Michigan Publishing Without music, life would be an error. —Friedrich Nietzsche The preservation of music in records reminds one of canned food. —Theodor W. Adorno Contents Member Institution Acknowledgments vii Preface 1 1. Late Capitalism on Vinyl 11 2. The Curve of the Needle 37 3.
    [Show full text]
  • THE DYNAMIC RANGE POTENTIAL of the PHONOGRAPH by Ronald M
    THE DYNAMIC RANGE POTENTIAL OF THE PHONOGRAPH By Ronald M. Bauman his article describes a new transmission standards of even lower added to the quietest passages by the approach for analyzing the quality than our current CD standards. cartridge-preamplifier combination dynamic range of the phono- Unless these standards are dramatical- should be essentially inaudible. graphic playback system, in which the ly upgraded (in terms of information Similarly, the cartridge-preamp sys- cartridge and preamplifier are treated content), we may never have a source tem should be able to clearly repro- as an integrated system. I analyzed of music for our homes that sounds ducd the loudest sounds on record the dynamic range potential of several better than the phonograph. without distortion, compression, or combinations of phono cartridges and Are analog records inherently better clipping. preamplifier amplifying devices and in some sense? Your ears may already The same should be true of CD compared the results to CDs. be telling you that analog can sound playback. The quietest passages Additionally, I speculate about the better than today's digital. I will should be reproduced without added drawbacks of frequency domain char- provide quantitative reasons this may noise or distortion of the rnusic acterizations of musical audio compo- be so. caused by amplitude steps, or sam- nents and suggest that the time pling intervals that are too coarse, or domain may be a more natural frame Qualitative Requirements by filter phase shifts and ringing. The of reference for audio instrumentation The subtlety of detail in the grooves of loudest peaks encoded, as for analog development.
    [Show full text]
  • High Bandwidth Acoustics – Transients/Phase/ and the Human Ear
    Project Number: FB IQP HB10 HIGH BANDWIDTH ACOUSTICS – TRANSIENTS/PHASE/ AND THE HUMAN EAR An Interactive Qualifying Project Submitted to the Faculty of the WORCESTER POLYTECHNIC INSTITUTE In partial fulfillment of the requirements for the Degree of Bachelor of Science By Samir Zutshi 8/26/2010 Approved: Professor Frederick Bianchi, Major Advisor Daniel Foley, Co-Advisor Abstract Life over 20 kHz has been a debate that resides in the audio society today. The research presented in this paper claims and confirms the existence of data over 20 kHz. Through a series of experiments involving various microphone types, sampling rates and six instruments, a short-term Fourier transform was applied to the transient part of a single note of each instrument. The results are graphically shown in spectrum form alongside the wave file for comparison and analysis. As a result, the experiment has given fundamental evidence that may act as a base for many branches of its application and understanding, primarily being the effect of this lost data on the ears and the mind. Table of Contents 1. List of Figures 3 2. Introduction 5 3. Terminology 5 4. Background Information 11 a. Timeline of Digital Audio 12 5. Preparatory 17 6. Theory 17 7. Zero-Degree Phase Shift Environment 17 8. Short Term Fourier Transform 20 9. Experimental Data 22 10. Analysis and Discussion 34 11. Conclusion 36 12. Bibliography 36 Page | 2 List of Figures 1. Amplitude and Phase diagram 6 2. Harmonic Series 8 3. Reduction of continuous to discrete signal 9 4. Analog Signal 9 5. Resulting Sampled Signal 9 6.
    [Show full text]
  • To: American Library Association ALCTS/CCS Committee on Cataloging: Description and Access From: Music Library Association Bibli
    CC:DA/MLA/2002/2 August 22, 2002 page 1 To: American Library Association ALCTS/CCS Committee on Cataloging: Description and Access From: Music Library Association Bibliographic Control Committee Subcommittee on Descriptive Cataloging Re: 4JSC/CCC/6: Expanded response to 4JSC/CCC/6 & Rule revision proposal for 6.5B to include optional conventional term qualifiers The Subcommittee on Descriptive Cataloging and the Bibliographic Control Committee of the Music Library Association have given consideration to the CCC proposal to revise 6.5B1 to record the specific format of the physical carrier using conventional terminology as the base rule and the current instructions as the option. Our initial comments were presented in an earlier document. This is a slightly expanded version, which includes our response to 4JSC/CCC/6 and lays out our counter-proposal in its entirety. Part I: Response to 4JSC/CCC/6 MLA adamantly opposes the CCC proposal as it currently stands. While we agree there is a benefit in introducing the possibility of more flexible terminology in Area 5, we strongly disagree with the suggested revisions. Our main reasons, with short discussion, follow. 1. Lack of adequate justification for the rule change The chief reason for this proposal, consistency of rules across formats, is inadequate justification for the magnitude of the proposed change and its consequences. Changing the rules of one chapter (or more) simply to parallel the rules of a different, unrelated chapter is flawed reasoning in and of itself, much less sufficient grounds for such a major revision. If we were to follow this logic, we would also need to introduce a rule revision for Chapter 2, so that the physical description could state “1 book” or “1 duodecimo.” The further justifying statement that the “revision will allow for greater flexibility, the provision of more meaningful information for end-users and the accommodation of information pertaining to new and emerging formats” is only partially correct.
    [Show full text]
  • Evaluation of Sound Quality of High Resolution Audio
    Proceedings of the 1st IEEE/IIAE International Conference on Intelligent Systems and Image Processing 2013 Evaluation of Sound Quality of High Resolution Audio Naoto Kanetadaa,*, Ryuta Yamamotob, Mitsunori Mizumachi aKyushu Institute of Technology,1-1 Sensui-cho, Tobata-ku, Kitakyushu 804-8550, Japan bDigifusion Japan Co.,Ltd 1-1-68 Futabanosato Higashi-ku Hirosima,7320057 Japan *Corresponding Author: [email protected] Abstract 1. Introduction High resolution audio (HRA), which is recorded in the digital audio format with high sound quality, appears on the In recent years, high resolution audio (HRA), which is audio market. HRA has the quality equal to or better than sampled at 96 kHz or 192 kHz with 24 bits accuracy, is the standard compact disc (CD), and is distributed as the becoming popular in the audio market. HRA is super audio CD (SACD), DVD-audio, Blue-ray audio, and commercially distributed as the lossless encoded file via the a data file through the internet. In this paper, sound quality internet, and is also available in the Blu-ray audio disc. of HRA is investigated in the view point of auditory Compact disc (CD) and lossy compression such as MPEG perception. Perceptual characteristics of HRA have been Audio Layer-3 (MP3) are the current major audio formats examined by listening tests as compared with the standard as the storage medium and the data file, respectively. As a audio CD and the compressed MPEG audio layer-3 (MP3) memory capacity increases and a wide communication qualities. The listening tests were carried out by the method network spreads out, HRA must be increasingly popular.
    [Show full text]
  • HOW TO, D, °;;Ti
    11 ° . i WORLDS LARGEST- SELLING'.,ÉLECTRONICS-MÁGÁZIh'Ee FEBRUARY 1978/$1 : °;;ti. T ° HOW TO, D, , .. rA Cá sette.71n arfacé tó On Elf Computer r ° - II' An_:.Átió'Blélrid-__,. ..tÁ.Coritról;to 'a- Hi -Fi Receiver - .,, The .V .1w: MicroMini Cassette Tape áfis ,Forx PC Guides Without Film or Ch micals! \\, ,0scar'scan: : 'Communications Satellites forr;Eyeryoné 1 , TESTÉD.T1-11S: ISSUE :Gárrard GT25 Turntable 1.',/({Sánsü-iAU-717.Stereó: Integrated Amplifier Slierwoód= Micro/CPU 100 Stereo FM Tuner Téñ;.Tec Century/21 CW Transce,iyer.,. 9' o _ L, 4Y-4: 50 , . 1. 4 3 ' 2 ADDRESS -- PROGRAMMER . 7 B r` P t'efi.. O 2 ' E LCPg= R w51"e"1- ,P ola 4,» °C. 41. I />FD°5 oo.ij v0 de> oldr .e>' oat, p 0 I 6 Z r`16 . V:y -nu; n.1 aa a0on311atiN Os79 Z0 ar 1130I11VO 1 . , - 6/MIN 01.411 060W05+9 961í0E of 14024 14278 ee ° Popular Electro rocs AmericanRadioHistory.Com Introducing the mobile that can move And ike all Cobras it comes equipped you out of the world of the ordinary with such standard features as an easy - and into the world of the serious CB'er. to -read LED channel indicator. The Cobra 138XLR Single Sideband. Switchable noise blanking and limiting. Sidebanding puts - p An RF/signal strength meter. And you in your own I SB LSr Cobra's exclusive DynaMike gain control. private world. A - d ' You'll find the 138XLR SSB wherever world where there's Cobras are sold. Wnich is almost every- less congestion.
    [Show full text]
  • Historical Development of Magnetic Recording and Tape Recorder 3 Masanori Kimizuka
    Historical Development of Magnetic Recording and Tape Recorder 3 Masanori Kimizuka ■ Abstract The history of sound recording started with the "Phonograph," the machine invented by Thomas Edison in the USA in 1877. Following that invention, Oberlin Smith, an American engineer, announced his idea for magnetic recording in 1888. Ten years later, Valdemar Poulsen, a Danish telephone engineer, invented the world's frst magnetic recorder, called the "Telegraphone," in 1898. The Telegraphone used thin metal wire as the recording material. Though wire recorders like the Telegraphone did not become popular, research on magnetic recording continued all over the world, and a new type of recorder that used tape coated with magnetic powder instead of metal wire as the recording material was invented in the 1920's. The real archetype of the modern tape recorder, the "Magnetophone," which was developed in Germany in the mid-1930's, was based on this recorder.After World War II, the USA conducted extensive research on the technology of the requisitioned Magnetophone and subsequently developed a modern professional tape recorder. Since the functionality of this tape recorder was superior to that of the conventional disc recorder, several broadcast stations immediately introduced new machines to their radio broadcasting operations. The tape recorder was soon introduced to the consumer market also, which led to a very rapid increase in the number of machines produced. In Japan, Tokyo Tsushin Kogyo, which eventually changed its name to Sony, started investigating magnetic recording technology after the end of the war and soon developed their original magnetic tape and recorder. In 1950 they released the frst Japanese tape recorder.
    [Show full text]
  • Digital Audio and Compact Disc Technology Second Edition Edited by Luc Baert, Luc Theunissen and Guido Vergult, Sony Service Centre (Europe)
    Digital Audio and Compact Disc Technology Second edition Edited by Luc Baert, Luc Theunissen and Guido Vergult, Sony Service Centre (Europe) NEWNES Newnes An imprint of Butterworth-Heinemann Ltd Linacre House, Jordan Hill, Oxford OX2 8DP *1§* PART OF REED INTERNATIONAL BOOKS OXFORD LONDON BOSTON MUNICH NEW DELHI SINGAPORE SYDNEY TOKYO TORONTO WELLINGTON First published 1988 Second edition 1992 © Sony Service Centre (Europe) NV 1988, 1992 All rights reserved. No part of this publication may be reproduced in any material form (including photocopying or storing in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright holder except in accordance with the provisions of the Copyright, Designs and Patents Act 1988 or under the terms of a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London, England W1P 9HE. Applications for the copyright holder's written permission to reproduce any part of this publication should be addressed to the publishers British Library Cataloguing in Publication Data Digital Audio and Compact Disc Technology. - 2Rev. ed I. Baert, Luc 621.38932 ISBN 0 7506 0614 2 Printed and bound in Great Britain by Thomson Litho Ltd, East Kilbride, Scotland Preface The past century has witnessed a number of inventions and developments which have made music regularly accessible to more people than ever before. Not the least of these were the inventions of the conventional analog phono- graph and the development of broadcast radio. Both have undergone successive changes or improvements, from the 78 rpm disc to the 33V3 rpm disc, and from the AM system to the FM stereo system.
    [Show full text]
  • The Dawn of Commercial Digital Recording
    The Dawn of Commercial Digital Recording Presentation by Tom Fine Audio Engineering Society, NYC Section June 15, 2010 © 2010 Thomas Fine. All Rights Reserved. The Dawn of Commercial Digital Recording Agenda: 1. Summary of ARSC Journal article (http://www.aes.org/aeshc/pdf/fine_dawn-of-digital.pdf) 2. Listening session/discography – some digital firsts 3. Discussion/Q&A © 2010 Thomas Fine. All Rights Reserved. The Dawn of Commercial Digital Recording Perspective 1. Commercial Digital Recording is now 40 years old. 2. Electrical Recording was 40 years old in the mid-60’s. 3. Tape Recording for Commercial Releases in the U.S. was 40 years old in the late-80’s. 4. The CD has been around since 1982 (28 years). © 2010 Thomas Fine. All Rights Reserved. The Dawn of Commercial Digital Recording Pre-History 1. PCM first described as mechanical facsimile system (Western Electric, 1921). US Pat. 1,608,527 (1926). 2. Ground-breaking research for electronic PCM voice transmission by Alec H. Reeves (IT&T, Paris, 1937). French Pat. 852,183 (1938) and US Pat. 2,272,070 (1942). Described but not commercialized. 3. Good summary in “Analog-Digital Conversion” edited by Walt Kester, Analog Devices. (www.analog.com/library/analogdialogue/archives/39-06/data_conversion_handbook.html) © 2010 Thomas Fine. All Rights Reserved. The Dawn of Commercial Digital Recording SIGSALY (1943-46) (http://history.sandiego.edu/gen/recording/sigsaly.html) First digital quantization of speech and first PCM transmission of speech – 12 terminals © 2010 Thomas Fine. All Rights Reserved. The Dawn of Commercial Digital Recording Early Digital Transmission for Broadcasting 1.
    [Show full text]
  • Download Chapter 1MB
    Memorial Tributes: Volume 14 Copyright National Academy of Sciences. All rights reserved. Memorial Tributes: Volume 14 THOMAS G. STOCKHAM, JR. 1933–2004 Elected in 1998 “For contributions to the field of digital audio recording.” BY ALAN V. OPPENHEIM THOMAS G. STOCKHAM, JR., professor at the University of Utah and widely regarded as the father of digital audio, died on January 6, 2004, at the age of 70. Professor Stockham was born on December 22, 1933, in Passaic, New Jersey. Tom was elected to the National Academy of Engineering in 1998. His career was strongly influenced by his love for teaching, music, perfection, and family and by his incredible skills as an engineer. He received all of his degrees in electrical engineering at the Massachusetts Institute of Technology and was appointed as an assistant professor at MIT in 1959. In the mid-1960s he joined the research staff at MIT’s Lincoln Laboratory, and in 1968 he joined the faculty at the University of Utah where he helped establish its computer science department. Early in his academic career at MIT, Tom worked closely with Amar Bose, founder of Bose Corporation, on the use of digital computers for measurement and simulation of room acoustics and for audio recording and enhancement. Through this work he became a pioneer in the field of digital signal processing, a technology that in the 1960s was totally impractical for real-time applications since the processors could fill (and heat) a room, and clock speeds were extremely slow by today’s standards. It was partly through Tom’s pioneering work on digital signal processing algorithms that this technology eventually emerged as critical to virtually all modern communication and multimedia systems.
    [Show full text]
  • The B.A.S. Speaker
    THE B.A.S. SPEAKER EDITOR-IN-CHIEF: Michael Riggs THE BOSTON AUDIO SOCIETY COORDINATING EDITOR: Henry Belot P.O. BOX 7 STAFF: Henry Belot, Robert Borden, Joyce Brinton, BOSTON, MASSACHUSETTS 02215 Dana Craig, Frank Farlow, Robert Graham, Lawrence Kaufman, James Lindquist, Peter Mitchell, John Schlafer, Jack Stevens, James Topali, Peter Watters VOLUME 5, NUMBER 4 PUBLISHER: James Brinton, President, BAS JANUARY 1977 THE BOSTON AUDIO SOCIETY DOES NOT ENDORSE OR CRITICIZE PRODUCTS, DEALERS, OR SERVICES. OPINIONS EXPRESSED HEREIN REFLECT THE VIEWS OF THEIR AUTHORS AND ARE FOR THE INFORMATION OF THE MEMBERS. In This Issue This months issue features an audiophiles whirlwind tour of (audio) Wonderland -- Japan. Peter Mitchell doesnt report seeing any white rabbits with watches or smiling cats, but he has seen such amazing sights as the Yamaha factory (one of them, anyway), a PCM audio recorder for consumers , and a new approach to ambience recovery that does not involve: (a) matrixing, (b) high-frequency whistles, (c) extra amplifiers, or (d) extra speakers in your listening room) The feature articles this time around are, straight from the horses mouth, the details on ARs computer digital delay system and from John Puccio a statistical look at the truth dispensed by the golden ears. We also bring you follow-up reports on Mike Riggs modified PAT-5 (impressive specs) and Bob Grahams treatment for acoustic suspension speakers (too much of a good thing?). Al Foster hooks up his test gear to a recent Sheffield record and likes what he sees as much as what he hears. Plus our customary collection of reader comments, classifieds, and periodical highlights.
    [Show full text]