newsletter VOL UME 9, NU~B ER 4 S UMME R 1982 P.O. Box 669, San Juan Capistrano, CA 92693 ©Oon & Carolyn Davis Ph: 714-496-9599 SYNERGETIC Working together; co-operating, co-operative SYNERGISM Co-operative action of discrete agencies such that the total effect is greater than the sum of the two effects taken independently. EXCHANGE OF IDEAS I met a man with a dollar I met a man with an idea We exchanged dollars We exchanged ideas I still had a dollar Now we each had two ideas SPHERICAL MAPPING FOR LOUDSPEAKER COVERAGE TABLE OF CONTENTS PAGE PAGE 2 SYN·AUD-CON EDITORIAL 18 HP-41C CLUB 3 HIS SOUND - WORKSHEET 18 TIME 3 SMI LE 19 THRESHOLD HEARING VS HEARING AT HIGHER LEVELS ( 4 A PROGRESS REPORT ON TEP" 19 MASK - MUSICIAN'S AMPLIFICATION SOUND KONTR~LLER 4 MODEL QA-200 ELECTR- ACOUSTl C ANALYZER 20 DECIBEL REFERENCE LEVELS 5 A CONCERT HALL ACOUSTICS SEMINAR 20 PZr1'~ POOl UM 5 SYN-AUD-CON HOSPITALITY SUITE AT AES 20 HP-41C - DEAD BATTERIES 6 SYN-AUD-CON 1982 AND 1983 SCHEDULE 21 SAN FRANCISCO CLASS MONTAGE 6 NEWSLETTER UPDATE 22 LEDEm "DOWN UNDER" 6 THE FAILS MANAGEMENT INSTITUTE 23 A BREAKTHROUGH IN DIGITAL ADVERTISING 7 TE P" AND ACOUSTI C MODELS 23 AUDIO PORNOGRAPHY 7 SMILE 24 SPECIAL COMMUNICATIONS SYSTEMS 8 LEVELS AND TIME DIFFERENCES 25 FLYING ENGINEERS 9 PHASE DISTORTION & PHASE EQUALIZATION 26 MINNEAPOLIS CLASS ~ONTAGE 10 C.. A. "Puddie" RODGERS 27 CALCULATING PERCENTAGES AND RATIOS 10 THE INITIAL TIME DELAY GAP 27 FILTER BANDWIDTH DESIGNATIONS 11 "QUORUM" TELECONFERENCING MICROPHONE 28 FINDING THE "RENARD SERIES" FOR FRACTIONAL OCTAVE SPACING 11 NEW "HI-FI FAD?" - THE LEDETM LISTENING ROOM 28 CONVERTING ACOUSTIC REFERENCE LEVELS 12 THE "REVOLUTIONARY" COPERNICUS SPEAKER 28 SMILE 12 FROf1 THE LONDON FINANCIAL TIMES 29 WHEN TO VARY LW VERSUS Q TO CONTROL La 12 DIGITAL ADDITION CIRCUIT 29 HAROLD W. LINDSAY - AN AUDIO GREAT 13 APRIL 1982 CLASS MONTAGE 30 "MANUAL FOR CRITICAL LISTENING" - AN AUDIO TRAINING COURSE 14 QUESTIONS REGARDING SAMPLING RATE IN DIGITAL AUDIO 30 BOOKS OF INTEREST 16 PZM® EXPERIMENTATION 31 CLASSIFIED TECH TOPIC: VOLUME 9, NUMBER 6 - LOUDSPEAKER ARRAY DESIGN WORKSHOPS - FEBRUARY 23-25 AND APRIL 20-22, 1982 SYN-AUD-CON EDITORIAL In traveling across this vast marvelous country of ours, we once again realized how great is the need for basic sound systems in the American lifestyle. Paging systems, background music systems, reinforcement systems, security systems, and many, many other forms of everyday communication are used in the communities we passed through. Many of the small communities we passed through are not large enough to support a profeSSional sound con­ tractor but do require church systems, school systems, restaurant systems, etc. We can't help but believe that there exists as a real opportunity a way to train a local man in each of these communities to act as ( a representative of your firm's capabilities to each of the local potential sound system users. Seminars for Church Laymen Some of our graduates conduct their own seminars for potential customers such as church members charged with the responsibility of overseeing their church's sound system. (HOWARD PARKER of Sound Investments in California has been successfully conducting such seminars for about 5 years.) These seminars are at a level that informs the attendee in very basic terms of the fundamentals he must know: 1. What are the key components of a sound system (microphone, ampl i fier, loudspeaker). 2. How are they interconnected (hi l, 10 l, balanced, unbalanced, etc.). 3. Choosing a microphone (omni, directional, high sensitivity, low sensitivity, etc.). 4. Choosing a loudspeaker (and, just as important, where to place it for most effective coverage with adequate acoustic gain). 5. Simple maintenance techniques (handl ing hum, noise, no-signal, and the basic substitution and isolation servicing techniques). Using today's very simple but extremely effective "signal tracers" can make this part of a layman's seminar very exciting. These simple seminars should not include any mathematics, should avoid any theory not directly experienced by the participants, and should provide each attendee with "hands on" practice in Walking over to a table with microphones, amplifiers, loudspeakers, cables and connectors and choosing from among them a system that he or she then hooks up and successfully operates. Large contractors cannot profitably service small systems but smaller contractors can and should, whenever they can, get the customer to come to them rather than incurring the expense of going out to find them one at a time. Send In Ideas Syn-Aud-Con would like to encourage our readers to send in their ideas about how to advertise such meetings, ( what the course content should be, and what sort of tools they feel should be provided. He will publish the best of these in future issues and share the successes you have in exploring how to better serve the audio needs of our rural and small communities. SYN-Aun-CON NEWSLETTER SIJ~MER 1982 HIS SOUND WORKSHEET MIKE GARRISON of HIS Sound in Portland, Oregon, has developed a 6-page worksheet Pulpit to front row seats Dothey have: cushioned seats II Pulpit to rear rowsoats _" ___ ~_" ~ custlioned backs LJ no padding l:l which is mailed out to churches over a Widthoffrontseatingarea ______" ___ Are rows: straight n angled [J curved I I Width of rear seating area (please illustrate on floor plan) Seating capacity ___ wide area, many of them in small towns Are seats: pews 1-] theatre type [I chairs r-l in remote areas. The worksheet, which Pulpit to front row seats Are rows: straight LI angled [J curved D is beautifully constructed to provide Pulpit to rear row seats Is seating area directly behind centered pulpit I-I Width affront scatlng area toonesideofplatformiJ(left __ orright ___ Width of rear scatlng area facing inwardly U detailed information, is reproduced here Seating capacity _ _ (please illustrate on floor plan) Arc seats: pews U theatre type L J chairs LI Do they have: cushioned seats I_I (one page) to show the detail. We are cushioned backs 0 no padding 0 asking permission of Mike to reproduce his worksheet in full as a future Tech Depth of seating area Do they have: cushioned seats 0 Width of front seating area cushioned backs [I no padding L I Width of rear seating area Are rows: straightn angled 0 curvedlJ Topic. We showed it to the Minneapolis Scating capacity ____ (please illustrate on floor plan) Arc scats: pews n theatre type LJ chairs 0 cl ass and they felt it was so important that DAVID WRIGHT (in the class) made Depth of seating area Do they have: cushioned seats 0 Width offrontseatlng area __ I cushioned backs [J no padding 0 Widttl of rear seating area / Are rows: straight I 1 angled n curved L I photo copi es for everyone. Seating capacity ___ (please illustrate on floor plan) Are seats: pews n theatre type 0 chairs n ------------------~ SMILE According to LARRY ELLI(lTT of Marshall nay A.ssociates of New Zealand, they have solved how to deal with incumbent politicians. At one of their "Wild Life" animal parks,lions and other wild beasts run free. Visitors drive through in their automobiles to view the animals as they feed and frolic. A sign at the entrance cautions against opening windows, forbids convertibles, etc. At the end of a lengthy list, it concludes with "Pol iticians on bicycles admitted free of charge." Larry Elliott, left, talking with George Owen, Chief F:nc)ineer at Pauland, and Harold Mosier, new General Manaqer at Emi lClr (back to us), during a break at the April Loudspeaker Array class. VOLLJ~1E 9, Nur~BER II A PROGRESS REPORT ON TEFTM The photo shown has historic interest in that it is the first photograph of an Energy Frequency Curve (EFr) on the ( Crown TEP" anal yzer prototype. Seeing the prototype in a partial functioning state left us hopeful of the eventual outcome but aware of the tremendous man-hours of work remaining to be done. The display screen is of sufficient size to allow easy viewing. The potential versatility being planned into this analyzer will be a challenge to all of us to use effectively in the exploration of new measure- ment parameters. MODEL QA-200 ELECTR-ACOUSTIC ANAL YZER During the San Francisco cl ass, ED LONG and RON WICKERSHA~ brought in and demonstrated the instrument that they make for qual ity control testing by the manufacturers using his loudspeaker designs. Ed makes a careful distinction between "Quality Control" and "Quality Assurance." "Quality Assurance" is what you do to check incoming components made by suppl iers for a manufacturer. "Qual ity Control" is the process employed to insure that your own manu­ ( facturing processes are producing the quality of product desired. E. M. Long Associate' s instrument for quality control testing of their loudspeaker designs. Anyone building a quantity of loudspeaker drivers or loudspeaker systems would benefit enormously from owning one of these testers. By merely pushing the five push buttons, tests such as: 1. Frequency response 2. Power response 3. Polari ty 4. Loudspeaker resonance frequency Ron Wickersham, left, co-inventor of many product 5. Impedance curves ideas that come from E. M. Long Associates. Ron owns Alembic. are all performed automatically. The tester has exceptional accuracy and more than adequate resolution. The price, in the $6,000 range, is realistic and the performance is far better than we have encountered in this type of instrument in the past. If you are in the market for a production 1 ine tester, we highly recommend that you contact Ed and Ron for further details as our description falls far short of all that this well-designed tool can do for a loud- ( speaker manufacturer.