Audio, Etc. (Dec. 1973)

By Edward Tatnall Canby

Four for Everything

'Way back last spring, I had a temporary experience that I have to describe to you. In fact I did, but the whole thing got put aside. And so here we go again. I found myself, all of a sudden, back on two speakers. And I didn't like it.

Not voluntarily mind you. I had every intention of listening to everything via four speakers from thence onward until doomsday. I am by now wholly adjusted to four-way sound for all listening, even mono broadcasts. And by last spring I was so accustomed to it that the very idea of trying out a good old-fashioned two-speaker set-up would not have occurred to me. Then, my quadraphonic amp conked, with no warning. All of it. Total silence. Now if there's anything I can't stand for long, it's total electronic silence. I fear I have joined the audio fraternity in this respect, for better or worse. So what? Back to stereo! Out with some of my old familiar equipment.

It was, I assure you, a most unexpected jolt, such as I wouldn't have believed. Phew! Only two speakers, both of them in the front of my room. After so long, I found this effect strangely unfamiliar and inadequate. I was really disturbed. The whole thing was so lopsided. All the music pushed over into one end of the room. Even when it was loud, it somehow seemed impotent; I kept turning it up too high. I was accustomed to the more gentle persuasiveness of four speakers, for more impact at less volume. Stereo was strident; quadraphonic purrs. The "dead" half of the stereo room really began to bother me. No speakers there! The rear of my listening space sort of dragged itself along, speaker-less, like a dog with its hind legs out of commission-ugh. All sorts of nasty things kept coming to mind. No--I did not enjoy my return to stereo.

The fact is that four surrounding speakers, given a minimum of differentiated sound, are more versatile, more flexible, capable of a much wider variety of sound impacts, than any two-speaker system, however hi the fi. The four-way surround speaker set-up is a basic advance in home listening over stereo, as stereo was (most of us will now admit) over mono. That is the big message that dinned itself into me. Astonishing.

But let me go back a bit. Things happen so fast. Before it conked, my four-way amp was one of those big single-unit "receivers," all of a piece, and it came from the matrix side of the quadraphonic fence, equipped with the then-new logic SQ decoder. I had been listening to SQ-type discs via this machine for some time-it was there, they were there; what better reason. Also everything else, including weather reports and the news. I duly reported to CBS that, unaccountably, my SQ news broadcasts were playing tricks on me. Invariably, the announcer's first syllable, in every sentence, came from the back speakers. But just as invariably, the next syllable came from in front. Odd! Perfectly intelligible, of course, but a quadraphonic side-effect I had not quite counted upon . . . (Note: my newest "three-chip" SQ logic decoder no longer performs this curious function. The newscaster stays put very nicely.)

CD-4? At that point, nobody had been kind enough to pass me a CD-4 demodulator, though RCA's discs had been coming in month after month. They got played, natch, via SQ. What else! Sounded nice, too. Then Elektra Records, which had just taken on the CD-4 system, offered me a nice new JVC demodulator. Excellent! In no time I had it plugged into the big quadraphonic machine (this was before it conked, you see . . .), the output going into the four "discrete" inputs handily provided at the rear. Even with RCA, so to speak, feeding Columbia, I figured it ought to work. It did. And so I was set for my first truly home experience with the discrete disc system, which until then I had heard only at numerous public demos. The Audio-technica cartridge, already in use in my system, picked up the 30 kHz carriers nicely, the red JVC signal "radar" went on and the music poured out. Great! Just superb, without so much as a minute of adjustment-it simply worked, straight off. How's that?

To be sure, the sound seemed a wee bit less discrete than I had hoped. But then, after all, ads are ads and we should expect a bit of a minus. So I quickly forgot that small feeling and proceeded to play straight through my modest pile of RCA Quadradiscs (this was before Elektra hit the market) one after another. I was happy. Like driving a brand new car first time around the block. But that was before I had discovered what I now must disclose.

It seems that my amplifier selector switch had been screwed tight at a wrong position. I hadn't noticed. I became aware of this when, one day, I was too lazy to get out my magnifying glass, lean over double, and read the fine print under the switch. Instead, I switched by ear-counting clicks.

HEY! Wrong number of clicks. The thing was one position off its base. In an instant the ghastly truth hit me.

When the switch said DISCRETE it was actually on SQ. I had been sending my entire "discrete" record collection through the SQ decoder, after demodulation via CD-4. And so I had me a gorgeously improbable sound, SQ logic working away upon a demodulated RCA signal! That accounted for my tiny little feeling that something was vaguely less discrete than I had hoped for in all those lovely RCA discs. It also, I trust, shows you how persuasive any four-channel sound can be, given a good recorded performance, well microphoned.

It was soon thereafter that this big amplifier conked on me. Why? One theory you can guess. Acute hysteria due to RCA/CBS confusion.

Another more rational theory was that perhaps the ultra-wide-range Audio-technica cartridge was throwing a blast of unaccustomed supersonics into the four amp channels, via the preamp. Worth a thought, though my reasoning tells me this wasn't the case in my case. Solid-state circuitry these days is nicely transparent to supersonics, even if your ears can't hear them, and one of these new CD-4 capable cartridges could, conceivably, send a really healthy micro-wallop straight into your system up in the high Hertzes. If the preamp doesn't blow, then the amplifier might object with an inaudible squawk of horror, not to mention the tweeters, if all else holds firm. JVC has a feed-through position on its demodulator, sending the pickup signal straight into the two-channel preamplifier for standard stereo sound.

Is there a filter somewhere en route? Seems to me there ought to be, these days, for safety. Worth a review, I'd say, of all present and contemplated playback equipment. The new CD-4 cartridges do send through the high stuff whenever it is there and they might indeed do damage or contribute to overloading.

Well, what actually happened to my amplifier was much simpler. We had an electric storm. Power went out. When it came back-no amp. Some sort of power surge and probably a healthy bolt of lightning (in spite of all my puny precautions). Act of God, I calls it.

And so, for weeks on end, until I went off on a vacation, I was limping along on two lonely speakers in "ordinary" stereo, like a four-cylinder buggy with two cylinders gone. Believe me, it's true. And not even the superb sound of the Crown 150 two-way amplifier system, pressed back gratefully into service, was enough to compensate for the lack of the other pair of speakers. That's how it was. I figure that in a few years' time all of us will begin to feel this way when we are reduced to a mere two speakers. Don't we feel it right now when we have to play through one living room speaker in mono? Sure, you can listen! But there is simply more information available, more aliveness, more versatility, in the quadraphonic array. You'll see. We'll learn.

Microstatic

So now I'm back in quadraphonics again, to my great relief. And I must add a postscript here that applies to all my four-way sound, whether mono, SQ or CD-4 or even home-recorded Canby-discrete via tape. Those four speakers. Just about this same time I got my first set of four identical units (I had previously used somewhat differing pairs, as most of us have to for awhile). These were the new Micro-statics, full-range units incorporating a new version of the earlier wide-dispersion Microstatic add-on tweeter system to give a complete hemisphere of equal highs out in front, both sidewise and up-and-down. Wide-angle dispersion in two dimensions.

Since we've already run detailed profile information on these units, I'll only say that for my ears, unaided by measurements, they are excellent quadraphonic speakers, rather gentle, not really the hard, big-bang sort good for rock music, but excellent for a four-way blend in a nice living room environment and plenty loud enough too. What is really interesting in them is that special dispersion of the highs, which works out to be extremely useful.

The tweeter array is zany; it sticks out in front of the box (and is covered by several alternatively shaped fancy grille covers, guaranteed not to collapse when you lean against them). It has to stick out, in order to get its extremely wide dispersion. That's the trick. It works. With four of these, you get a smoothly uniform spread of sound from any point within the listening area, no matter where you are-as you move, you are astonishingly unaware of the individual speakers. No "beams" to walk in and out of. No special best spots. This is definitely all to the good and highly desirable.

But the nicest feature of the Micro-statics, to my mind, is the separate level control for the front-facing tweeter unit (there are a number of tweeter cones, combining their coverage for the ultra-wide even spread). Turn this down, and you "blunt" the front of your sound hemisphere, the sides remaining intact. The volume is less , straight out in front, than it is off to the sides. You use this unusual feature if you habitually find yourself too near one speaker, hearing it too noticeably above the others. With the front turned down in this way, you can be right next to the speaker and still not hear its highs separately--unless you lean over and stick your ear almost into it. Amazing. And yet, via the continuing side dispersion at normal volume, your over-all room balance remains intact in the rest of the listening space. Simple and very ingenious, I say, and good thinking.

In view of prevailing arguments concerning methods of sound dispersion in the listening room, it's worth noting that these Microstatic speakers do not depend on reflected sound for their smooth, any-place-in-the-room blend.

Wherever you may be, you receive direct signals from all four speakers, radiated equally over the hemisphere of space in front of each. Stereo (and quadraphonic) theory is clear enough: the stereo effect itself, whether by two channels or four, depends on interaction at the ears between signals set apart in space and coming from different directions. Reflected signals are less desirable than direct, simply because the more they are reflected, the more diffuse and, hence, uncontrolled is the stereo.

A pleasant blur. Room reflection is, of course, an inevitable part of our listening and we allow for it in the art of recording; but it is never more than a passive drag on the controlled, intended stereo interaction. Real stereo-real quadraphonic-comes from direct-line hearing, speakers straight to ears.

Four channels, surrounding the listener (to get back to where I started), offer a factually greater control of the listening space than two. Active sound sources all around, and no passive rear area, merely reflecting what's up front.

Six simultaneous stereo "pairs" instead of only one. (Front, rear, left side, right side, two diagonals.) And all working simultaneously. The more we keep these interacting signals direct and uncluttered by reflection, the stronger will be the quadraphonic impact. That's why I favor the sort of direct-line dispersion offered by the Microstatic speakers, as well as by other speaker systems of a similar design philosophy.

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So you like your old two-channel stereo sound? OK! Fine! You are by now wholly used to it, comfortable with it, tuned to it; you have learned to read it. One does have to learn, you know. It has taken you a long time, though maybe you haven't even noticed. I'm only telling you that the same is likely to happen when you shift to four. For everything.

(Audio magazine, Dec. 1973; Edward Tatnall Canby)

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