THE SOUND ENGINEERING MAGAZINE JULY 1969 75c Television Sound: Panel Discussion The TV Audio Mixer West Coast AES Picture Gallery www.americanradiohistory.cominrmnriii works, aad works aod works aod works Take a look through control and audition rooms of the stations in your community and count the number of Rek-O-Kut turntables that keep going and going and going. Minimum maintenance, practically no repair. Faith- ful, reliable sound. Year after year after year. Ask those station engineers how long they've had Rek-O-Kut in- stalled. You'll find some of those turntables have been around a long time. Rek-O-Kut turntables are built to take it. They are sim- ple in design and operation, strong in construction. If you have a Rek-O-Kut now, we'd hardly be able to sell you a replacement. But we'd like to sell you another! soecilications; SPEEDS: 331/3, 45, 78 rpm. NOISE LEVEL: -59db below 5 cm/sec average recorded level. MOTOR: custom-built computer type heavy- duty hysteresis synchronous motor. 45 RPM HUB: instantaneously re- movable by hand. PILOT LIGHT: neon light acts as an "on/off indicator. FINISH: grey and aluminum. DECK DIMENSIONS: 14 x 15%". Minimum Dimensions: (for cabinet installation) 17%" w. x 16" d. x 3" above deck x 6Vi" below. PRICE: B-12 GH Turntable $124.95. S-320 Tonearm $44.95. Optional BH Base for audition room $18.95 . KDSS KOSS ELECTRONICS INC. 2227 N. 31st Street • Milwaukee, Wis. 53208 Export: Koss Electronics S.r.l. Via Bellini 7, 20054/Nova Milanese, Italia Export Cable: Stereofone Circle 60 on Reader Service Card www.americanradiohistory.com ""I Coming • John Borwick, noted British writer' has contributed the first of what will be a series of European newsletter-type articles. It's title is Dolby Revisited. Robert C. Khle has a new article on electronic music systems called a Real Time Computer Synthesizer System. A Common Bass Mixer—Filter Amplifier, is the title of a circuit article by W alter Jung. And there will be our regular colum- nists, George Alexandrovich, Norman THE SOUND ENGINEERING MAGAZINE H, Crowhurst, Arnold Schwartz, and Martin Dickstein, coming in db, The Sound Engineering Magazine. JULY 1969 • Volume 3, Number 7 Table of Contents About FEATURE ARTICLES The Television Audio Mixer Marshall King 19 the Panel Discussion; TV Sound 24 Picture Gallery: West Coast AES Convention 28 Cover MONTHLY DEPARTMENTS Letters 2 The Audio Ensineer's Handbook George Alexandrovich 8 The Feedback Loop Arnold Schwartz 12 Theory and Practice Norman hi. Crowhurst 16 Ed torial 18 Sound with Images Martin Dickstein 32 The db Bookcase 34 Classified 35 People, Places, Happenings 36 EDITORIAL BOARD OF REVIEW George Alexandrovich Sherman Fairchild Norman Anderson Prof. Latif Jiji • Dramatic lighting enhances the clean Daniel R. von Recklinghausen lines of this console photographed at William L. Robinson Paul Weathers the Audio Designs booth at the West John H. McConnell Coast AES Convention. In the photo Q_ above. Audio Designs president, Robert O" Bloom (closer to the camera) is explain- db, the Sound Engineering Magazine is published monthly by Sagamore Publishing Company, Inc. Entire contents ing the features of the console to noted Sagamore Publishing Co., Inc., 980 Old Country Road, Plainview, LI., N.Y. 11803. Telephone recording engineer William Robinson audio-visual,_i. 733-6530. sound db reinforcement, is distributed consultants,to qualified videoindividuals recording, and firmsfilm sound,in professional etc. Application audio—recording, must be made broadcast, on an O subscr| tl0 forr or -o (behind). The AES Picture Gallery PiU. b.en Possessions, P Canada," " and on Mexico) a company in U.letterhead. S. funds. SingleSubscriptions copies are 75c$6.00 each. per Controlled year ($7.00 Circulation per year postageoutside at haston. Pa. 18042. Editorial, Publishing, and Sales Offices: 980 Old Country Road, Plainview New York begins on page 28. 11803. Postmaster: Form 3579 should be sent to above address. www.americanradiohistory.com bv the audio engineers to produce a Robert Bach PUBLISHER high-quality sound is beyond all criti- cism. From microphone to mixing con- Letters sole to high-quality audio monitors, Larry Zide every effort is made to produce the best EDITOR quality sound possible. But even this high-quality sound is Bob Laurie for nought when received by the av- ART DIRECTOR erage monochrome or color receiver. For now we come to the real culprit, Marilyn Gold the tv set manufacturer, who in the COPY EDITOR interest of economy has cheapened the audio portion of the receiver to the Charles N. Wilson point where the end result is barely ASSISTANT EDITOR passable. One may ask, why doesn't The Editor: the public complain about this poor Richard L. Lerner I have been following your articles on audio? The answer is simply that the ASSISTANT EDITOR the quality of tv audio with great in- pubic has been fed so much poor quality on am radio that the sound of the aver- terest. A. F. Gordon Mr. Canby implied in his article in age tv set is far superior to the pocket- CIRCULATION MANAGER January that the audio portion of the transistor sound that the listener ac- tv broadcast is not always what it cepts everyday. An interesting parallel exists in the elimination of the d.c. Eloise Beach should be. Here is the only point on ASST. CIRCULATION MGR. which I can agree with him, but not for restorer in that same monochrome set. the same reasons. He states that "the Here again the set manufacturer is to audio signal in television should be blame, he is again saving perhaps a rigidly perfect, or as near to perfection dollar a set by eliminating d.c. restora- as the art allows." But he then reverses tion in the picture. And yet, the lack his position and gives a multitude of of proper gray-scale rendition in the reasons why it is almost advantageous, picture is neither missed nor lamented nay mandatory to have low quality by the general viewer. tv audio! Mr. Canby certainly must Now instead of giving aid and com- know that there are certain FCC fort to the tv manufacturer by agreeing SALES OFFICES regulations governing the audio portion that no improvement in audio is needed nor desired, Mr. Canby should be in of the tv broadcast that must be ad- New York hered to. For instance, minimum re- the forefront of those audio purists 980 Old Country Road quirements for the sound portion of who demand only the highest-quality Plainview, N.Y. 11803 the tv transmitter are a bandwidth of sound with their pictures. But no, Mr. 516-433-6530 SO to 15,000 hertz with a harmonic dis- Canby introduces his "audio-visual tortion of not more than 3.5% and a mix" to prove what we need is worse Denver signal-to-noise ratio of at least 55 dB. audio to match a "tiny, fuzzy little tv Roy McDonald Associates, Inc. This would certainly seem to conform picture." If Mr. Canby is used to seeing 846 Lincoln Street to Mr. Canby's original statement. this kind of picture, I can only suggest Denver, Colorado 80203 Therefore, any poor audio quality must fixing his old set or getting a new one. 303-825-3325 come from a prior source. Television For it has been proven in literature audio comes from three main sources, that our tv system is capable of trans- Houston optical tracks on film, magnetic sound mitting excellent high-quality pictures. Roy McDonald Associates, Inc. 3130 Southwest Freeway (either film or tape), and finally "live" Schade of RCA proved long ago that Houston, Texas 77006 sound from the studios. Let us start our 525-line picture can be the equal of 713-529-6711 with optical sound for two reasons; 35 mm. motion picture film in terms first, over half of the audio on tv comes of picture sharpness.- Mr. Canby con- Dallas from film, and second, Mr. Canby inti- fuses sharpness with definition, al- Roy McDonald Associates, Inc. mates that it must be of high quality though there is very little relation be- Semmons Tower West tween the two. He admits on one hand Suite 411 to match "the sharpness and definition" Dallas, Texas 75207 of the movie screen. Yet if Mr. Canby that "it is obviously an adequate 214-637-2444 had done his homework he would have standard for a vast range of entertain- found that optical soundtracks have ment and useful message transmission." limited bandwidth (8000 Hz on 35 mm. But he then states that "tv is Hatly San Francisco lo-fi" (without defining his terms) and Roy McDonald Associates, Inc. and 6000 Hz on 16 mm.), suffer from 625 Market Street relatively high cross-modulation and this is absolutely untrue. It has been San Francisco, California 94105 other distortion, and have poor transient proven that the fidelity of the tv system 415-397-5377 response. In addition, it is common in such objective terms as aperture practice to compress and limit the response, light-transfer characteristics, Los Angeles average track so that everything comes signal-to-noise ratio, etc., is the equal Roy McDonald Associates, Inc. out at the same level. So if optical sound of 35 mm. film.- Mr. Canby continues 1313 West 8th Street Los Angeles, California 90018 is transmitted, it certainly is not de- that since tv is "lo-fi" it deserves audio 213-483-1304 teriorated by the tv transmission sys- with less density than the picture. He _>• tem but is rather marginal to begin mentions the audio-visual mix" as the reason for this which he says has to do Portland with.