Audio, Etc. (Apr. 1973)

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Walking Pan Pot

I’ll tell you one thing about working with the new semi-pro home-type four-channel tape recorders. You must keep yourself bodily orientated.

At all times and without deviation! Otherwise you are lost. I should know.

You have to turn yourself into a sort of animated pan pot, ready to move front right, rear left or what have you, in a fraction of a millisecond.

It's like the points of the compass, diagonally. Imagine those four loudspeakers out there, NW, NE, SE, SW, surrounding you. You read the controls on your orientated machine the way you read a road map to chart the road ahead, but even more rigidly. You do not "drive" your tape machine in any direction except straight ahead and forward, looking towards the front.

I once knew a city boy who could not read maps in a car except when we were driving North. When we went South he had to turn the map upside down in order to figure where we were going. I laughed at him and he was furious. But he still turned the map upside down. It's like that only worse if you try driving your new four-channel recorder in any way except in the one correct orientation, facing FRONT. And I say this, knowing that many an advanced recording engineer will not even recognize a front or a back in his four-channel work. Even so, one must face somewhere, somehow or other, and I say that one should orientate one's self, one's thinking and one's machine to a common directionality-whatever you choose to call it.

Turn yourself around, or your machine, and in moments all is directional chaos. You'll grab the wrong control for the wrong channel-and it's back to the beginning and try, try again.

You must think orientation, and act it. You do it directly in space, whether actual or projected in the mind. Ignore the fancy channel terminology! It's deadly, and must be translated into action-which takes thought. It's a tangle of nonsense at this stage--LF, RR, L1, L3, Channel Four, Two, A, D, B-a nightmare. You'll never get anywhere if you think in these terms while you are actually working with tape. (Fine for the algebraic theorists on paper.) Instead, what you do is simply to point. Don't call your channel anything. Just look at it.

Point out diagonally with your left hand. That's the front left channel, yes? On your machine it will be the upper left hand VU meter in the cluster of four. Right? No label needed.

Just a spatial correspondence. So also with the controls, visible and tactile.

Every one of them for that same channel must be the upper left in a clump of four. And the same with the all-important signal lights. Record that channel, and a red light goes on in the upper left corner of the clump of four.

(Well yes, the space isn't quite literal, UP being forward. But you can make it literal by tipping your machine over to the horizontal, or halfway, if you really need to.) And so it goes.

No thinking. No translation.

Oh, so you must plug in a cable for that left front channel? Ah, yes. The inputs are in back. So you get up and go around for a look-STOP! Stay put.

Instead, reach over, or around, and do your plugging from your same orientated position. On the two TEAC machines, as previously noted (the 2340 and 3340), the backside inputs and outputs are laid out to correspond to your up-front orientation, so you can in fact stay put, facing front, and do your plugging by feel exactly as you read your controls and "see" your speakers. It's a good idea. I cannot vouch for the Sony four-channel recorder, not having examined its rear, but I can definitely say that this useful orientation should be adopted by all forthcoming semi-pro four-channel equipment with backside plug boards.


If you defy me and look directly at the TEAC's rear, thus reversing your spatial field, you will find everything laid out backwards. Left, you will see, is to the right, and vice versa. Good! Serves you right (left). Let's call it Canby's Rule. In all four-channel work, stay orientated.

Line up your body, your thoughts and your machine with the ultimate playback and keep them that way.

Canby's Rule applies to four-channel space as the Canby Constant (AUDIO, May, 1972) applies to the fourth dimension, time.

Since my last piece on the new home-ish semi-pro four-channel taping, I have found myself in some new and interesting configurations. What does one do, for instance, with a four channel machine on a public stage? (Take note of this, you professionals.) I gave a lecture/demo at the University of Oregon, part of a Festival of the Two Visions, more commonly known, after C. P. Snow, as the two cultures.

The arts and the sciences. As always, I found myself just halfway between the two and that is why I was there.

Predictably, my subject was "Toward One Culture". I never did think there were two. Also predictably, I put on a four-channel demo, which took place in a large and properly reverberant auditorium in the Music Department.

With still further predictability, I filled that saintly musical space with outrageous sounds not normally listed as music, all grossly amplified at 150-foot spacing (more or less) out of four enormous Voices of the Theatre, kindly provided by the management. It may not have been a musical evening but it most certainly was sonic.

Now wasn't it nice that the management also provided me with a TEAC 3340, its four-way controls identical with those on my more inexpensive TEAC 2340 at home. In all that strange space, I was thankful for the familiarity under my fingers. Came my rehearsal time and there it was, hooked right up to the four monster speakers and neatly set out on a table next to my lectern so I could talk to the audience and have it close by for the demo-but hey! It was backwards. And come to think of it, so was I. Facing rear.

For a moment my head whirled. A whole evening (for me) in reversed quad? Canby's Rule screamed NO. The lecturer, after all, must face his audience and therefore he looks towards the rear of the hall. And at the rear speakers. Everything is reversed. Right channels are left, back channels are front.

Well, actually, I had faced this problem elsewhere. I'm a choral conductor, you will remember. In chorus concerts I face the audience to talk about the music we will sing. But when it comes to conducting the singers, I turn my back like any proper conductor. (That's why conductors-though not me-wear tails. They look so nice from the rear. And, incidentally, they let your shoulders and arms move.

That does help, I'll admit. I have a special suit coat with knee action, for my own arms.) So, as you can quickly guess, I "conducted" my four-channel machine. I set it up behind me, as I faced the audience, and during playback I monitored gain on the big speakers with my backside to.

I had to. It was absolutely essential that my own physical orientation line up with the normal directionality of the reproduced sounds, so that my hands on the level controls would react automatically, left, right, front, rear. Be warned if you ever run four channels from a stage.

By the way, in that large, reverberant hall my demo was restricted to specially selected four-way sounds, and no regular quad music, though as always the temptation to put on a quadraphonic spectacular (with such enormous speakers!) was strong. I cannot say too often that public demos of recorded music in big halls are an unmitigated waste of time, creating more confusion than sense; and it's no different with quadraphonic. The normal recording is designed for home reproduction in a small enclosed area, the traditional living room. (Or maybe inside a car.) There, it re-creates a large space inside a small, intimate surround, and that is the entire rationale of the acoustics involved. (This applies as well to the synthetic space of the modern pop disc.) Play your recording, however, into a second large space, a big hall, and you have acoustic chaos, one big-hall sound inside another and a disastrous double liveness.

With rare exceptions, the sound is dismally bad and the recording is much better left unplayed.

The only normal music I used, therefore, was a Canby Singers stereo tape (as made last year on the Nagra IVS), which I copied off on the spur of the moment through a just-arrived Electro Voice EVX 44 decoder, thus making four channels out of two. Good idea.

Make your own quadraphonic tapes from stereo. It worked in playback, in this case, because being church music the sound was actually improved by the double liveness-a fine "cathedral" effect. It was a brief anthem by Thomas Morley (of "My Bonnie Lass She Smileth" and "Now is the Month of Maying"), sung by only ten singers, and as it soared voluminously out of those four big Voices of the Theatre I wondered to myself what old Thomas M. would think. I expect, prosaically, that he would not even recognize his brainchild. But I thought it sounded fine. I am, so to speak, a child of today, and this is the way we "translate" older art, older music, into the modern media languages for our present ears. It's all right! as the Beatles say.

"Henry". a few years back, was my first mixed media show in multiple, done with three channels of pictures and four of sound, the latter distributed via two separate stereo tapes; for we had no semi-pro four-channel equipment then. For my Oregon demo I copied off the two original "Henry" tapes onto one common four-way tape via the TEAC, and it was a pleasure, so utterly easy after more than three years of hit-or-miss coordination via two entirely separate tape machines.

The old two-tape system worked OK, but it was a pain in the neck, requiring two operators what with the necessary gain riding for public presentation. (I could never manage both machines by myself. I'm too scatterbrained.) So to get the whole thing onto one tape, securely tied down ,and synced to perfection, the levels correct and nothing but one button to push, was a thing to be thankful for. I must say once again that this new four-channel sync technique is superbly useful for the home tape experimenter, and for the pro who uses his own semi-pro equipment. There's no end to the useful things you can do.

For those who are not pros, here's the way it's done, or I did it. No, you don't have to play all your sources simultaneously. Copy them oft' one at a time. I started with the front-speaker tape for "Henry". It had been made on my big two-track stereo machine at 7 1/2 ips and I played it on the same, copying conventionally onto tracks 1 and 3 (the front tracks) of the TEAC tape. Without the second tape to bother me, I was able to concentrate on the right levels for this material, making good corrections as I went through it. Then-reel back to the beginning and start once again.

The back "Henry" tape wasn't even compatible with the front. It had been assembled from assorted four-track recordings made mostly on a battery portable machine at 3 3/4 ips (and not bad in sound, considering), a montage of all sorts of persuasive noises, from crickets and katydids to rushing automobiles around a small-town traffic circle, double-speed, and running-water Niagaras, half speed, out of my kitchen faucets. To get this onto my TEAC tape I set up a different machine, four-track, and fed it into tracks 2 and 4. Our original arrangement required periodic re-cueing of this tape, at points marked by white leader, while the front tape played on continuously. So it had to be re-cued in the copying.

Problem? Not a bit. You can stop and start your four-channel sync machine anywhere during recording without a trace of a click or a thump. So--copy the first segment, stop the tape, re-cue, go on with the second, and so on, and no editing needed.

For the sync operation I switched the front channels, I and 3, into sync playback via the top two of four little slide switches right on the front of the TEAC heads, in the proper orientation.

Then flip the front-channel RECORD switches-same orientation-to OFF, and the rear channels, the bottom two, to ON. Now when motion starts the back channels will record and the front pair play back through their recording heads, in sync with the incoming signals. You hear the whole works, just as it will sound when the finished tape is played. And you can monitor the gain on the two recording channels, while listening to the playback of the other two. (You could copy without sync, of course, by putting all four channels into normal playback since this is a "three head" recorder, four channels to each head. But you would not be able to monitor the levels on the incoming signal except via the playback, which would of course be delayed. Chancy. Or if you listened directly to the record input signal the sound would be out of step with the playback of the rest.) When all is ready and all switches double-checked, you shift the transport lever into PAUSE, the center position, and push the RECORD button. Nothing moves. But two bright little red lights, the bottom two of four, go on.

Once again, the correct spatial alignment, for instant seeing. You are ready to record the back two channels.

First you must jack up the playback volume on the synced playback, the front channels, already recorded. Sync playback on the TEAC machines is 'way down in level as compared with normal playback through the playback heads. An annoyance but presumably necessary for economy in this complex but inexpensive machinery. I have it roughly calibrated; you move the play volume up about two and a half notches for sync playback, to read approximately accurate levels on the meters. (I plan to do a more exact calibration by trial and error, and I suggest that TEAC might recommend a figure in its literature. Also, they just might be able to incorporate some extra amplification, which would automatically compensate for the difference. It would be very useful.) And so you are off. Flip the lever from PAUSE to PLAY and the recording/playback begins, just as you have pre-set it. Now you can (and I did) concentrate on the proper levels for the second recording, while listening against the front playback. I use headphones, by the way. They bring you all four channels, two for each ear, and you can flip to front channels only, or back channels, to see what each is doing. Almost easier than working with four actual speakers.

If anything goes wrong, you can always reel back and start again. Anywhere. No clicks, no pops.

In my most recent show, produced on the TEAC machine last summer, I ran into some horrendous mixing problems (horrendous for a non pro, at least ... ) trying to assemble my four-way montages of pre-recorded voices, plus music via SQ decoding, sometimes one signal to a channel, sometimes in pairs front/rear, or even diagonally like an X. With all this complexity, every single "take" required total orientation, plus a check-through of dozens of switches, meters, cable connections, to be sure all was set right.

It was here that my strong conviction grew that one must line one's self or and directly sense the four channels, minus intervening terminology, for any sort of efficient operation. I worked out all sorts of odd refinements on the idea, to help myself.

For instance, when I wanted to record in diagonal pairs of channels, I would place a highly visible piece of sticky tape right on each of the two meters I would be using for one diagonal, and another set onto the relevant volume controls. I could then see my diagonals at a glance. Say, upper-left-to-lower-right. Left front to right rear, that is. I would even go so far as to hold my hand out at a diagonal slant in front of me--it goes that way, I would soundlessly mutter to myself. Then, the first diagonal safely down on the tape, I would reel back and set things up for the opposite diagonal, including all the switches and those pieces of sticky tape, which would now read very visibly "upper right-to-lower-left". It really helped.

In putting together the more complicated spoken ensembles I even went so far as to stick people's names on the corresponding meters and level controls. David front right, Mary at left rear, Dorothy up front on the left. There they stood, or their names stood, in the very configuration in which they would speak, via the playback speakers! Sounds silly, but my work went much faster after I had put this Canby's-Rule system into effect.

Instant orientation by direct, visible tactile means, and no terminology at all. It's the only way when you are supposed to think of a dozen things at once.

I don't know how the pros work in their hundreds of thousands of dollars' worth of quad studio space, but I'll guess that they have long since worked out more sophisticated versions of my own sticky-tape system. I'm sure that the more buttons and meters and levers you have to play with, the more quickly must you learn instant operation, minus thought. Every good control console I have seen is expensively laid out in patterns, for this very sort of work.

Well, 'nuff said. It's a brand new technique, this sync thing, for us amatooer recordists, but I'm here to say that it should spread, and spread fast, as more four-channel sync machines appear to supplement TEAC and Sony, the first to hit the market.

In a way, it plays straight into the home tape user's hands-for there is no editing. Most tape machine owners are notorious for their lack of editing know-how. They won't touch it. Now they don't have to. Everything is done by levers.

Imagine it. I myself have spent more than twenty-five years becoming a very expert tape editor, via hundreds of assembled radio tapes and plenty more of my own choral recording sessions, assembled by the classic joining of different "takes" into finished wholes. I must have put down a hundred million white splices in my day.

And now--a whole four-channel extravaganza under my belt and not a single splice! I don't know whether to laugh or cry. Better a good laff, I guess. I'm having fun with this non editing and in the process I'm getting so orientated that I'm practically a walking pan pot, LF, RF, RB and, er, Channel Four. A good feeling.

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

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