Behind The Scenes (Aug. 1972)

by Bert Whyte

EVERY YEAR come June, it is time for the Consumer Electronics Show in Chicago. The arrival of this show is always greeted with mixed feelings. It is nice to see many old friends in the industry, and while all the shiny new equipment has its undeniable allure, the thought of what one has to endure to see this equipment, gives pause. Last year the show merely occupied the main floor of McCormick Place. This year, the CES management has proudly announced that the entire lower floor has been used for exhibitions as well. Well, friends, that adds up to ... hold your breath . . . an area equivalent to 20 football fields! I can tell you that this rotund reporter isn't going to take in every exhibit ... not unless they furnish me with a golf cart. Oh, well ... a lot of the stuff isn't in my purview, and some of the more exotic hi-fi stuff is always demonstrated in the undeniably better acoustic conditions in the local hotels. McIntosh, Bose, Crown, and Harman-Kardon are among those which will hold forth in the hotels.

If the CES last year was slanted towards quadraphonic sound and Dolby noise reduction, it is the same this year, in spades! Everybody but everybody is showing quadraphonic receivers, amplifiers, pre-amps, open reel decks.

Dolby cassette decks are legion. The astonishing aspect of all the quadraphonic equipment is the great numbers of units which incorporate the SQ decoder circuitry. Astonishing, because SQ is not industry standard, nor is any other matrix system, and especially so in view of an apparently very viable RCA/JVC discrete disc. The proliferation of the SQ equipment must be viewed as a great compliment to the power of Columbia software. They have the name artists, they have released or announced more quad recordings than any competing system, and as a result the list of Columbia/ Sony SQ licensees grows ever longer.

Amidst this sea of SQ quadraphonic equipment at the CES are the RCA, JVC, and Panasonic islands, strongholds of the discrete disc. In the light of recent developments of the discrete disc and demonstrations I have attended, it seems obvious that far from us getting an industry-standard four-channel disc, the battle lines have been drawn anew, each side has called up their reserves, and the issue is still very much in doubt. Apart from the two main contenders, there is a very significant new development in decoding techniques from Sansui, about which I'll tell you a bit later on. Since the CES pretty well sets the hi-fi merchandising plans for the year, it would seem that at the very least, the matrixing and discrete forces will co-exist. Quite apart from technical considerations, and with all due respect to colleagues Len Feldman and Ed Canby for their expositions of the reasons for and methods of combining the discrete and SQ systems onto one disc, I don't think the two industry giants are going to give an inch to the other side on this point.

Somehow, the big boys never learn from experience. Years ago, when the RCA 45 rpm "doughnut disc" was fighting the Columbia 33 1/3 LP, it should have been obvious that the 45 was ideal for the pop single market, and the LP for the album and classical market.

But no ... and it is my understanding that in the 18-month "war," the outcome cost RCA some 8 million bucks! I mentioned earlier some developments on the discrete disc. I attended the Midwest Acoustic Conference in Chicago in April, which this year was devoted entirely to quadraphonic sound. There were some interesting talks by the great tape recording pioneer, Marvin Camras, and by John Volkman, both concerning quadraphonic sound fields and their perception. John Eargle outlined his quadraphonic processing techniques, while Bill Putnam talked about studio quadraphonic recording techniques and the Cooper Time Cube delay unit I reviewed last month. There were other relevant talks on various aspects of quadraphonics and finally there were the discussions and demonstrations from the matrix disc proponents and from the RCA discrete camp. Well, it all started off in gentlemanly fashion, but at the conclusion of the conference, when both sides were answering questions from the floor, there were some indignantly raised eyebrows, then some raised blood pressures, and things got a bit warm! Without taking any sides or casting any aspersions on anyone, in my opinion what started to stir up things was a very dramatic slide presentation and sound demonstration on the discrete disc by RCA. What some factions had undoubtedly felt were very difficult, if not insurmountable problems with the discrete disc, had apparently been resolved. We were shown scanning electron microscope photos of the grooves of a discrete disc at tremendous magnifications. One such picture was the equivalent of looking at the grooves of a disc seven miles in diameter! On the grooves of the disc you could see the tiny peaks and valleys of the supersonic signal.

We were shown photos of discs that had been played as much as 200 times with a conical stylus at 5 grams tracking force. There was easily visible evidence that a large proportion of the supersonic signal was worn away.

Then the disc was played with a JVC magnetic cartridge and through a demodulator and into four amplifiers and speakers. Sure the disc was noisy, with high hiss and plenty of ticks and pops . . . BUT nonetheless we still heard four discrete channels of sound! How come? Well, the RCA/JVC boys had come up with a new type of demodulator, employing phase-lock loop circuitry, just the same as is appearing on the fancy new breed of FM tuners now reaching the market. With this very sensitive type of demodulator, the supersonic signal on a discrete disc can be down as much as 18 dB and can still be picked up and activate the circuit. In addition to the new demodulator, a special record compound with a new type of lubricant incorporated in it was developed. The compound itself is harder than the standard vinyl record. In combination with the new type demodulator, it would appear that this has solved the wear problem that many feared would erase the carrier signal on the discrete disc after relatively few plays. Needless to say, although other problems remained to be resolved with the discrete disc, this dramatic breakthrough on the wear problem caused considerable consternation in the matrix camp.

Jerry Orbach of JVC was kind enough to furnish me with a CD-4 magnetic cartridge with the new Shibata stylus (a somewhat chisel-shaped affair that purportedly tracks more accurately than an elliptical stylus), a demodulator, and some discrete discs. Incorporating this into my system was a simple operation, and I have been playing discrete discs now for some time. My reaction is generally favorable. The four-channel stereo is excellent, with rock-solid localization of instruments. The normal parameters of frequency response, distortion, and dynamic range were reasonably well preserved. I hedge a little here, because I feel that low frequency response is off a little, due probably to the 11.33 rpm cutting speed which is presently necessary to cut the high frequency carrier onto the lacquer.

One of the records I received contained excerpts from Hair. It so happens that I also have the discrete four-channel stereo cartridge of Hair. While the excerpts are slightly different, it was easy to make a comparison, and the disc certainly is as discrete as the cartridge. In fact the disc is to be preferred to the cartridge, because it is much quieter. I must say that someone had better look into Dolbyizing the Quad-8 cartridges. In the home listening experience, the noise is just too distracting. Later on I received the first of the RCA discrete classical discs, a melange of such items as the Sorcerer's Apprentice, Night On Bald Mountain, etc performed by Ormandy and the Philadelphia Orchestra. It would seem that Mr. Peter Munves of RCA took heed when I complained about the phony classical stereo for, praise be, this disc is a true four-channel stereo recording with rear channel ambience ... and well done too! In addition to the as-yet-unresolved problem of broadcasting a discrete disc, the other alleged shortcomings of the JVC disc are said to be a reduction of level and the amount of time that can be cut on a side. The reduction in level would appear to be valid, although variable.

On the pop discs I have, the levels seem to be down 2 or 3 dB in comparison to a standard RCA stereo recording.

However, on the Ormandy classical disc, the level was down by as much as 5 or 6 dB. Bass response was also down, and the fundamental of the bass drum lacking, as was its impact. The Hair recording was approximately 22 minutes on a side, and RCA now claims they can cut as much as 26 minutes without significant level or bass reduction. This level business and the timing still seem to be problems with the discrete disc, but as with the breakthrough on the wear problem and the way things appear to be moving, I would bet that these will soon cease to have significance. Unquestionably, the discrete disc is impressive, and despite some of the aforementioned problems, it must be taken seriously as a major contender in the four-channel disc sweepstakes.

Just to add fuel to the already brightly-burning four-channel fire, Sansui has come up with what appears to be a very substantial advance in matrixing technology. At the Los Angeles AES convention, some of us were invited to a private demonstration at a nearby hotel. A discrete quadraphonic tape was played for us, and then A/B-ed with a disc cut with the Sansui QS encoder and decoded through a new type of decoder. The results were startling. With both pop and classical selections, there was very little apparent difference between the tape and the disc. Localization and separation were very accurate and stable. Ambient material was as effectively reproduced as "surround stereo." There seemed to be little of the diffuse "amorphous" feeling typical of much matrixed quad sound. Details appeared in the July issue and the new technique involves the use of a rotationally symmetrical, variable decoding matrix (Sansui names it Vario-Matrix), controlled with the phases of the two encoded channels. The Sansui encoding system remains the same as before. This new technique is strictly in the decoding end. With it, channel separation of 15-20 dB is claimed between any pair of speakers.

It is claimed that the symmetrical electrical and acoustic characteristics, both front-to-back and left-to-right, enable one to locate sound in a full circle or at the dead center of a sound field. What I heard was impressive and while I would have to live with it awhile to sort out any idiosyncrasies, it must be reckoned as a matrix system with great potential. All this intense activity on the four-channel front tells me we are going to have a very exciting New York Hi-Fi Show, come Sept. 26th!

(Audio magazine, Aug. 1972; Bert Whyte)

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