"PEAR PRESSURE" (an essay about psychoacoustics)

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We are tremendously concerned today, when audio communication is merging ever more inextricably with the visual, as to exactly how the human senses work-the ears, the eyes, the mind itself, and especially, all three together. This involves all sorts of ancillary combined perceptions in which it is hard to tell where, so to speak, the eyes and the ears begin; in nature they invariably work as one and with them the mind, which infers such things as space, location, distance, size, direction, and even reality itself. (And now there is the "virtual" image.) We are working everywhere in the relevant sciences today, but nature is still well ahead of us. We take the complicated scientific way; nature is casual, instantaneous, direct. What a contrast! Unbridgeable? Not quite. We are getting places.

A perception that any old normal human body can make in so many seconds without the slightest calculation may take years of study to re solve into some sort of predictable scientific exactitude. Painful! Scientists who deal with perceptions in the human system are even worse off than the medicos who study diseases. Perceptions cannot be seen or heard. Nor even described in easy words that are scientific. Good! What does that mean? Good HOW? Yet the experience itself is so simple, so direct. We live with our perceptions, and we must marvel at them. Unbelievable, when you think about it. And so effortlessly accomplished! We must really envy our own perfection, a fait accompli, laid down a million years ago and still in place, before we can even start our tortuous science. Yet now is the time when it seems we really are getting things together. By which I mean, ever closer, more useful relations between direct human perceptions and measurable engineering parameters that can explain and, more important, predict how those perceptions will work. Selectively and analytically. This is the very essence of scientific method.

You will note that the 95th Convention of the AES, the Audio Engineering Society, which was held in all its enormity October 1994 in the Big Apple, made all the above essentially its theme, though not in so many words. "Audio in the Age of Multimedia." That is, how do we bring together sound and sight and more? Together with a reasonable subtheme, audio-only, the newest research into hearing, listening, auralization, that being a recent new term that may be ugly but is no doubt useful. (Another I had not seen was codec, not related to codex. I'm still working on this one, though I do grasp a certain algorithmic slant to it.) An astonishingly large segment of the AES sessions was given over to such matters as psycho- acoustics, and others even more "perceptual," al ways the relations between what we see and hear and the scientific analysis of the same. Good old familiar AES areas--such as signal processing, recording, and assorted distortions-barely hold their own. We have more important things to untangle.

Note too that in Europe the 12th AES Conference was held June [1994] in Copenhagen, exploring very much the same exciting new areas of basic research, if on a much more intimate scale. Judging by accounts (and pictures), the animated talk in Copenhagen never stopped. It went on day and night over coffee, wine, champagne, and maybe even Coke.

Somehow, you see, the advent of digital audio, though late, opened up such huge, almost infinite new areas for our expansion-like, say, four channels to 1,000 or plenty more-that an intense new wave of research into just how we hear, and see and think, was set off. How we have floundered in the past, particularly in connection with that all-natural art, music! Floundered in concert halls, made progress in stereo, but on the whole without too much successful, interrelation between nature and science. Now, we start to go.

Nature is simple-or so it seems. Nature is direct. It is much the same with our most pervasive audio "message," the art of music. It is indeed all-natural! To a musician, music is not a thing that has to be explained: It is. (Or should be if it isn't.) In its way, music too is simple and direct, no matter how verbose the accompanying publicity. Camille Saint-Saens, as you will often hear, observed that he produced music the way a pear tree produces pears. Has anyone yet synthesized a pear, via scientific research? Maybe, with gene splicing, you could create a pear for the market out of soybeans? Maybe, but nature does it better. And quicker. As an art, music of any kind shares much with nature and the operations of our perceptions. Music is indeed a product of those very perceptions.

Take rhythm. Some people have it more than others. I have a lot, and as a sometime conductor, it comes out of my hands as well as the rest of me. The other day I took a test for blind spots due to glaucoma. Phew! The engineer who designed that computerized machine was no musician. The machine accurately zeroes in on the blind areas via flashes of light, small bright circles that you either see or don't see, and maps them out via computer feedback- immensely ingenious. But the damn thing has rhythm! It goes calunk, da-dah, calunk, da-dah, and you are supposed to press a button when you see a dot. No, I didn't tap my feet to this beat; I kept pressing the but ton in time with it-involuntarily. Until I thought to ask the technician to slow down to half speed. That gave me time to think, not merely perceive, and so defeat my own senses. See what I mean? Many musical experiences are more complicated than that. But though they are often learned, over long periods, they work in the same all-natural way. Instantly, with out thought. There is nowhere in the adaptation of music to the current age that has seen more scientific floundering than in the design of new, modern (in style) concert halls, supposedly by scientific calculation for the most desirable acoustics.

We began, after World War II, with the brave but hideously misguided Royal Festival Hall in London, which almost instantly built itself a dreadful reputation among musicians. What went wrong? Do I need to tell you? Lack of rapport between musical perceptions and scientific analysis of the causes of those perceptions!


Long before that, in the mid-'30s, our own audio engineers and their architect colleagues collectively stuck 'their heads into an even worse sonic morass. On the nice theory that a dead "studio" would al low a, maximum of musical clarity and a minimum of blur and confusion (reverb), they built NBC Studio 8H for Toscanini and the NBC Symphony. Totally dead. And very large. Every detail was thought of (except one); even the programs were printed on sheer silk, so there would be no noise. (What they had to ignore was the human cough. No cough drops.) Was there ever a more total discord between the all- natural art of music and the all-engineering broad profession? Eventually, NBC got the message. Toscanini was moved to Carnegie Hall, not scientifically designed but New York's best, even so. My children, reverberation- noise-is a part of music. By now all audio people know this, and so we progress.

As you may know, the Royal Festival Hall led to the still-young art of synthetic concert hail reverberation. A scurrilous story says that one great German conductor, who was horrified, came back a few years later and pontificated that the building's surfaces must have weathered and mellowed, to produce such an improved sound. Do you know the rest? It was the surreptitious electronic reverb, the very first. Deliberately, it was kept a dark secret.

Not so with the much heralded Silva Hall acoustics in Eugene, Ore., of a dozen years or so ago, the first building designed deliberately for electronic reverberation. Christopher Jaffe, who improved on the Festival Hall electronics, was the designer of this superb building's three-way system. Eugene's multimillionaires love publicity, and pay for it. At first they were ecstatic. But now the place is, acoustically, a wreck. When a few misguided musicians objected (true, they could not hear themselves well enough, an understandable oversight for a first try) and then the local symphony conductor came out adamantly against the whole thing and refused to play unless the electronics were entirely turned off, the local paper printed a scathing attack that I found really agonizing. So much worthy effort gone to naught! Last I knew, the entire electronic system was turned off, inoperable. Concerts are simply held without it, and listeners don't like the sound. Why should they? Now, you must go to Alaska ( Anchorage) to hear a newer incarnation of the Jaffe system. If it is still working, that is.

You know, engineers and scientists have their perceptions too, their special sorts of instinctive genius. Einstein, the tax collector. Richard Feynman, that prankster and humorist from Brooklyn, one of the century's real mathematical, scientific geniuses--all-natural, you might say.

I repeat an account of some years ago. I then thought, and still think, that Christopher Jaffe's huge "portable" outdoor sound system for the New York Philharmonic and Met Opera is an unheralded stroke of genius in our field. By ingenious delay lines, a genuine stereo impact over acres and acres of New York parkland without any sense of walls or borders, and evenly wherever you may listen. Who else has produced such a remarkable sound?

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