This year, the annual Los Angeles convention of the Audio Engineering Society
was later in May than usual, and the CES in Chicago was earlier in June than
usual ... resulting in over lapping reports which I hope doesn't cause too
much confusion. Herewith the second part of the 63rd AES convention report
... the CES report will follow. I've fairly well covered the digital doings
at the 63rd, and while it is all very exciting and glamorous, a tour of the
exhibits and demonstration rooms was convincing evidence that the audio industry
is still firmly en trenched in the world of analog.
It has become a cliche to report that new mixing consoles were shown by those specialist firms, which inevitably, at every AES convention, show new mixing consoles. But there they were, new offerings from the likes of Neve, Quad Eight, Automated Processes, Solid State, MCI, etc., in all their awesome complexity. I recently did a mix on a 30-input board (a modest unit these days) and can readily testify that when the Good Lord gave us 10 fingers, He didn't reckon with modern mixing consoles.
Analog tape recorders are very much with us, as witness the latest models from such stalwarts as Ampex, Studer, MCI, etc. New to the professional ranks, however, was the Otari MTR-90, a 16- or 24-channel recorder using standard two-inch tape. This unit does not employ a pinch-roller with its direct-drive capstan, with a phase-locked, closed-loop servo system con- trolling capstan and reel motors for constant tape tension. The MTR-90 features fast wind modes in which the capstan remains engaged, which is said to produce a very smooth tape pack. Tape speeds are 15 and 30 ips, with wow and flutter at 30 ips of less than 0.03 percent (DIN 45 507) while S/N ratio on the 24-channel version at 30 ips is rated at better than 62 dB. Frequency response at 30 ips is listed as ±2 dB from 50 Hz to 20 kHz. Remote control is available, as is an auto locator for search and cue. Bias record frequency is a comparatively high 246 kHz, and headroom is rated at + 24 dB. Price for the 24-channel MTR-90 is around $32,000.
Computer Cutter
It is always interesting to see new disc-cutting equipment, since it is comparatively rare. The new light weight Cybersonics disc-cutting lathe, which I reported on at the last Los Angeles AES convention, has now reached the production stage with five systems said to be available. The lathe displayed was fitted with the Ortofon cutter head. The Sontec Company of Cockeysville, Md., attracted a great deal of interest with their new "Compudisk" CD-80 digital lathe control system. Essentially, it is a device for automatic groove pitch and depth control, operating in the digital domain. Using programs of slope analysis and phase analysis, the system uses a high sampling rate to analyze the modulation envelope and computes optimum groove pitch (lines per inch) and depth, stores the information in a memory, and a servo system executes the commands of the computer-generated motional profile for maximum groove packing density on the record. (This is a very simplistic explanation of a highly complex process.) The system is claimed to be self-analyzing on turn-on for all operational parameters. A display panel shows time elapsed for individual bands as well as cumulative for the en tire side, and has an indicator of groove depth and another to indicate pitch. The "Compudisk" system has built-in half-speed cutting ability. The system can be retro-fitted to all older models of Scully and Neumann lathes.
Clay Barclay of Barclay Analytical Systems, Wynnewood, Pa., was justly proud of the first production models of his Badap 1 audio micro-computer.
The functions of this unit are myriad and much too complex to fully discuss here. A few of the features are the displays which are multi-colored on a nine-in., single-gun color picture tube.
All labels and graticules are synthesized by the computer and, with the standard NTSC color output pro vided, can thus be also displayed on larger screens including projection types. This also permits videotaping of the display data input. The Badap 1 has many applications, among them, real-time analysis, peak-versus-average mixdown control display, tape-to-disc transfer, tape recorder alignment, and cartridge and tonearm alignment. One of the programs now available is automatic computation of RT/60 reverberation time. In conjunction with this, the unit will perform chromatic spectral analysis, another form of room reverberation measurement, where in stead of measuring a single third-octave band at a time, all 31 bands are analyzed simultaneously. The Badap 1 is a most versatile instrument, with many unusual capabilities, and after its long gestation period, it is good to see it reach production status.
Speaking of products a long time aborning, Sansui finally made its entry into the professional audio field with the introduction of their B-1 power amplifier, E-1 disc pre-amplifier, and P 1 parametric equalizer. Sansui took a group of ye audio critics to the Westlake studio in Hollywood where the new equipment was demonstrated.
The amplifier is a 250-watt-per-channel brute with the rather astonishing specs of a 300 volts-per-microsecond slew rate and rise time of half a micro second, all, of course, in the interest of minimum TIM. Their special "diamond-differential, direct-coupled" circuit is said to be responsible for these impressive figures. I hope I'm not counted as an "old curmudgeon," but frankly, with my antipathy to screaming rock music and the harsh, "tizzy," peaky sound typical of most studio monitor speakers, which is how the units were demonstrated, honest evaluation was impossible. All the Sansui equipment looked very professional and imposing, and their human engineering aspects well executed. I expect good things of this equipment when I get a chance to hear it under my own controlled listening conditions.
Speaker Systems
That there is an alternative to the "colored," raucus sound of most studio monitor speakers was amply demonstrated by the ACD John Meyer Studio Standard Reference Monitor. John Meyer is a very bright young engineer, who particularly espouses a purist philosophy in his audio designs. John has designed and built much of the specialized input equipment for the direct-disc recordings of Crystal Clear Records. He has acted as systems engineer on the direct-disc recordings I made with Virgil Fox, the Boston Pops, and the London Philharmonic Orchestra. John's approach to studio monitor speaker design is of the "no-holds-barred," "no compromise" variety, and the system consists of two speaker cabinets, each 21 1/2 x 15 x 30 1/2 inches, with specially configured horns and 12-in. cone woofers. A separate control unit houses four power amplifiers, electronics crossovers, and amplitude-and phase-correction networks. Each speaker weighs just under 100 pounds.
The systems are bi-amplified, and the design is partially a result of research by John at the Institute for High-Fidelity Studies at Montreux, Switzerland.
The speakers are, in fact, manufactured in Switzerland. To complete the system, there are the 400 ES sub-woofers driven by a special two-channel amplifier. As you have guessed by now, the complete system is on the large side! The monitor speakers alone have a claimed frequency response of ±3 dB from 27 Hz to 18 kHz. A rise and settling time of 500 nanoseconds is claimed to eliminate transient smearing, and the power handling is prodigious .. . a continuous 115 dB with no thermal losses. Below the crossover point of 100 Hz, the subwoofers will put out a staggering 8 acoustic watts continuously! Now if you can imagine that kind of output, with a sound that is neutral and uncolored, with no low frequency "boominess," you'll under stand why this system created such a stir of interest with many engineers.
Count among those impressed Stan Ricker of the JVC Cutting Center, Dr. Tom Stockham, and yours truly.
Unfortunately, such all-out engineering is expensive. The complete ACD John Meyer system will make you $11,000 poorer. Of course, that includes all the power amps, crossovers, etc. On the other hand, some of our high-end audiophile speakers, with appropriate electronics, are in that same rarefied area. As you can readily understand, speakers like this are unlikely to be on display at your local high fidelity emporium. For information on them, you can contact John at Meyer Sound Laboratories, Inc., 2194 Edison Ave., San Leandro, Calif. 94577.
The phone is 415/569-2866.
For some reason, this AES convention had lots of activity in loudspeakers. Bob Fulton's FMI company was at tending their first AES and showing the Fulton "Premiere" speaker. This is an evolutionary concept derived from the Fulton "J" series, and it now must be rated one of the most outstanding audiophile speakers on the market.
Poor Bob Fulton wasn't around to show off his triumph, being laid low in Minneapolis with a 104 degree fever.
However, I saw Bob later at the CES and heard more of the "Premiere"; I'll go into details in the CES report.
For the last of AES speaker news, we visit the Cerwin-Vega room, quite deliberately isolated from the main area of the convention, for therein holds forth genial Gene Czerwinski, "High Priest of High Levels." Gene has always been noted for manufacturing speakers with high output, and, as you can imagine in this era of "disco sound," he has been particularly ad dressing himself to this market. Gene uses various kinds of horn-loading in his systems to generate high-efficiency bass. Coupled with monster 18- and 24-inch woofers are speakers Gene calls "Strokers." He places pairs of these units "nose to nose" ... woofers facing woofers ... on the front left and right of his fairly large room, adds high efficiency mid-ranges and tweeters, and bi-amps the whole array with some 4000 watts of power! Using some of his own Sony PCM digital recordings for super-quiet source material, he turns this decibel demon loose! My Gawd! Have you ever experienced 30 to 40 Hz frequencies at sound pressure levels over 130 dB? The wave fronts literally flap your trouser legs for a free dry-cleaning. Your chest and head feel compressed. To me, exposure for more than a few seconds is unthinkable, yet the 'disco devotees apparently soak this up by the hour. The amazing thing is that in spite of this awesome output, the signal is clean. Gene had his demo room partitioned, and in the front part, his speaker design philosophy executes a 180-degree turn. There he was playing his highly sophisticated audiophile speaker, a line source, with an array of spiral-on-thin film transducers, some 76 of them, plus sub-woofers. Since I also checked this out at the CES, I'll give details later.
As usual at the AES, there were many other items, but space won't permit. Before we wrap up the 63rd AES, however, it is worth noting that for the first time, the cocktail party preceding the banquet was held out side in the pool-side patio of the Hilton, with a Mexican mariachi band, no less! I had a ringside table, and when you heard the sound of the trumpet, two fiddles, and three guitars, with all its power, dynamics, and emotional impact, you realized that with all of the glittering panoply of sophisticated audio equipment in the exhibit upstairs, we are still quite a long way from capturing the true essence of the live musical experience!
(adapted from: Audio magazine, Sept. 1979; Bert Whyte)
Also see: Behind The Scenes (Aug. 1979)
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