Audio, Etc. (Jul. 1973)

Those Channels.

After some eighty or so years we still use the inherently faulty spiral disc groove, rather than the inherently superior groove on a cylinder. We haven't yet finished our work in catching up with the asymmetrics of disc performance. The inherently faulty swiveled tone arm, too, is still with us in spite of admirable progress towards tracking perfection chez Garrard and others. It is always the same story: (a) the disadvantages can gradually be minimized and (b) they are balanced by emphatic advantages in the incidental or side characteristics of the mechanism: (c) the "disadvantages" may often be turned to profit, as with the minimal literal realism of two-way stereo reproduction. Stereo is much better than merely literal.

Our present arguments between matrix and discrete, (both in theory and practice) are basically along these traditional lines, and are not unlike those concerning disc vs. tape over many years. Tape is in ideal respects a better sound medium than the disc (though not as "better" as we once thought); and yet tape had enormous disadvantages, and very nearly died of them in the consumer market not so long ago. Oddly, you see, the tables often turn (bad pun) to aid the theoretically superior product out of its practical secondary inferiorities! In the very struggle for existence, tape has made astonishing progress against serious problems, notably in mass production, not to mention the fi/speed ratio and the S/N factor. Again--same story: inherent disadvantages are gradually reduced, allowing inherent superiorities to emerge and grow.

And so there may be a constructive see-saw effect in the coming years as between matrix and "discrete" systems of LP disc encoding--always remembering that a total, radical changeover, to something on the order of the new TV discs, would involve millions of dollars' worth of sudden incompatibility and the vanishing of the entire present phono structure and its century of cumulative progress.

The matrix-discrete see-saw could bring the slower-developing "discrete" system to the fore because it is inherently superior in some basic respects. Its disadvantages have already given rise to constructive advances--tougher discs, the excellent (but tricky) Shibata stylus, new wider-range cartridges-all of which will feed back into the whole audio industry, for whatever hi-fi we may produce.

Meanwhile, the matrices march on because they are, even further, in the great aesthetic tradition of the art of recording. You complain that many SQ quadraphonic recordings are made especially to fit the SQ virtues and to avoid its weaknesses? Isn't that the very art of recording? What else? We no longer, for instance, walk our stereo opera stars around the stage in (two-way) stereo because in playback it was found that they seemed, rather, to float like fat balloons through the operatic air, or to fade out of one place and into another in a disconcerting and most unrealistic fashion. We play up discrete stereo separation, without motion, because it works. We use our medium for what it can do, and we find new things for it to do well almost every day. If making use of the convenient matrix's capabilities, and avoiding--its faults, is wrong, then let's get back to concerts and "live" stages and forget recording.

Finally, keep in mind that what is most important for today's listeners isn't quadraphonic recording at all, on disc or tape-it is four discrete channels in the home. For all sound, of any type.

Once you are accustomed to that superiority, once the effect of four is familiar and comfortable, you will not go back to two for anything, any sound. How do you think I listen to mono news broadcasts and sports? How else but four-way! I listen to all my music, radio, records, tape, via four channels. I find the superiority of the four-way reproduction of standard (two-way) stereo is so great, that I no longer really want to listen to any standard stereo via two front channels alone. I can, of course. But I don't. I've found something better for my present discs and all the rest.

Even without a single quadraphonic recording in my home, I now would be sold on the four-way home system, and that is from personal inclination after a number of continuous years of it.

Take this as a prognosis for those who are a bit behind us reviewers and specialists in terms of length of experience. We are now, so to speak, in mid-1975; we've been into four-way listening for a long time. Take our word for it! In this frame of reference the actual quad disc (or tape) is an added frill, a very definite advance-in-detail over the impressionistic musical effect of standard stereo via our four-way systems. But what matters (yes--you equipment people!) is the playback equipment we have and are accustomed to, the hi fi in every corner.

For my money, you can plug that until you are blue in the face and I won't mind a bit.

Mighty Mite

No, it's not Mickey Mouse. Just another speaker. The impulse to build small speakers, remember, is always with us and will not die. It led, after all, to the present not-so-small "bookshelf" systems. (I sometimes wonder how that term has managed to persist.

Have you ever seen a bookshelf that would take a bookshelf speaker?) That impulse, having produced bookshelfers with optimum parameters, still continues. Let's shave off a bit of performance and make it even smaller; or, more constructively, let's try again and see whether we can't have even more of our cake and eat it too. One product of such thought is this tiny box called Mightymite, of which I have a pair on hand.

This is by no means the only small heavy duty speaker around, especially if you move up in size just a bit, a few inches here and there. But it does represent some interesting extremes in the parameters. Wow! It measures 11 by 6' by 7 and is it heavy. Massive, stone-dead chipboard with wood grain Formica over it, two speakers inside, each with a 1 1/4 inch voice coil, and a whopper of a pair of magnets totaling 24 ounces and 28,000 maxwells (it says). How big are the drivers? I can't see 'em but they appear to be all of four inches wide each. Whizzer mechanical tweeter attached in front of each.

How do they sound? Loud! All I can say, is that as a stunt I detached my big back speakers and inserted these babies (sitting on top), on each side. Up front were two AR 3a monsters, with added Micro-static wide-angle tweeter distributors on top of each. Some comparison! To be fair, I jiggered the tone controls, putting the back lows on full boost (imagine what that fed into the babies in the rear) and rolling off the ARs, until I had a rough tonal balance between front and back. The Mightymites (that's their TM) proved to be more efficient than the ARs in their proper middle range and I had to adjust volume too.

Once all this was done, I proceeded to listen to four-way sound for a number of days on this addled system with no pain at all. A switch from back to front would show up some difference in color and, of course, there was no bottom bass on the Mightymite spectrum. (It gets to .60 Hz pretty well, though.) But as to volume-nobody would believe what those babies will take. I haven't blown them out yet, though I have tried. The original specs called for 22 watts R.M.S. power handling, but that has been upped to "10-50" watts, after some not-so-discreet experiments with a Phase Linear amp. I put in thirty good watts, if my amp specs are right, and it came out LOUD. I wouldn't say the Mightymite is the hi fi man's answer for ultimate sound. I suspect that some of the speakers that are, say, merely twice as big, can produce a better over-all sound spectrum though, by golly, I'll bet it won't be any LOUDER. But if you are intrigued by this highly ingenious new try towards having that very special speaker cake, super miniaturization, you had better listen here.

And do not confuse this speaker with those zillions of even small affairs mounted in semi-cardboard streamlined boxes with snazzy grill covers which, alas, go under the name of Hi Fi in these unlicensed days. The Mightymite is interesting because it is so definitely not in that category; it is a real component speaker, its only oddity, and its resulting performance, being the extremes of its chosen parameters. If it weren't so oblong, I'd be tempted to call this one an audible cupcake. (Well, maybe a pound cake.) Made by Priority Electronic Corp. in New York.

Two per ear

Now look! I wouldn't for the world want to risk being an old fashioned spoil sport and I am surely no pessimist. But I just don't think it will work. I refer, of course, to the newest form of four-channel listening. So economical. Two channels per ear. Right up close.

Now I could be wrong, and I hope, if so, that you manufacturers will tell me so in reasonably polite terms. No offense intended just pure scientific questioning. But if I am right, then I also trust that somebody in the sci-fi community will, please, back me up and quick. I may need the help. And if any advertisers are advertising these things in our magazine, I do indeed beseech them to keep RIGHT ON, and don't stop just because of me or anything, for goodness' sake. As I say, I might be wrong and I am not a scientist, just a writer type, BUT--Well, how can I say it? The way you perceive a front left signal is by the usual dual-purpose teaming of two ears. There is a phase difference between the signal reaching each ear which indicates a source to the left; and/or there is a volume difference for similar result. A signal, however, which is heard in one ear only has no spatial directionality whatsoever.

Listen to a loudspeaker with one ear covered tightly and you are unable to locate it at all. It is everywhere and nowhere. It takes interaction between two ears to produce the basic sense of direction.

How about forward vs. back? That is a more subtle thing by far, as those who have studied binaural recording know (and see my own article on the same). It is, if I am right, partly by context, first of all. Never underestimate context! Like the symphony orchestra, many sounds are up front because you see them up front. You know they are there-so how could you hear them in back? Also, front vs. rear would seem to have to do with the complex shape of the ear flaps, which do much to differentiate sounds from forward and rear. Also, still further, with your particular head shape and ear spacing, plus your own unique ear flaps. Somebody else's head and flaps won't do at all, for you. This might account for some perplexing failures in experiments to design a surrogate head for binaural listening. Nobody to my knowledge has yet really produced an accurate, trustworthy binaural reproduction of sound in terms of fore and aft.

OK. So now you are about to feed four channels into two ears, the right pair exclusively to the right ear, the left pair exclusively to the left ear.

Double binaural, I'd call it. Definitely not stereo, mind you. There, each ear hears all the channels, whether two, four or umpteen. In this new system, you are simply feeding a pair of binaural right-left signals into one set of ears.

Yes, of course you'll get a right and a left differentiation. Both pairs of channels will give you that, one superimposed on top of the other. Two ears, working together, for an effect that is already familiar enough in plenty of private listening. What I ask, though, is if the left front channel is fed to the forward part of a small enclosed space around the left ear-and nowhere else--and the left rear channel is fed to the rear portion of that same small enclosed space, does that ear hear forward-and-back directionality? Well, there you are. I say it's spinach and to heck with it. But again, I might be very wrong. All I know is, if you don't hear forward and back in that small enclosed space, to go with the side-to-side perception, then you sure aren't hearing quadraphonic sound.

You're just receiving four channels paralleled into two. Something like a quadraphonic disc played on a two-channel stereo system, only binaural.

Did I hear somebody mutter something about head phones? Don't look at me. I haven't even mentioned the term.

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

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