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Will it make for a cheaper and simpler stereo - with, say, one woofer instead of two? Or will it make for more expense - with three units instead of two? Do you get better stereo in the same space, or just-as-good stereo in a smaller space, or is the idea to provide, without limit of cost, the absolute ultimate stereo in an even larger spatial set-up? Let the comparisons dangle! Does it cost "more" - or "less"? Phew. I'm really confused myself, having interviewed a number of different promoters of variants on these themes and having studied some literature and a lot of advertising.

I'll end up, this month, with observations on one particular commercial embodiment of the three-speaker principle, but in general my approach, so far, has been to play my cards close, to avoid foreign entanglements, so to speak, to do my own experimenting, such as it is, via home-made approximations of the various principles being promoted.

I'm scarcely beginning, even now, though as early as last winter my assistant and I were tinkering in utter ignorance with a center-speaker hook-up that finally produced precisely no sound at all, when we got the two amplifiers in balance. The good old A - B principle!

You can find this neatly described, along with a number of decidedly better ways to go at things, in our October 1959 issue, thanks to the boys at Pilot (p. 23, and see the big ad on p. 39).
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• Anmerkung : Wie man hier zwischen den Zeilen lesen kann, wußten auch die amerikanischen Redakteure sehr genau über den Zusammenhang zwischen redaktionellem Artikel (Inhalt) und begleitender (oder "flankierender") Werbeanzeige Bescheid.

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That article is a required technical addendum to this discussion and, may I say, we have just completed here in my home-and-castle a Pilot-type alteration of a non-Pilot amplifier which should provide three "bona fide" channels for three equal speakers, with the middle one A + B, non-cancelling. But I haven't had a chance to try it yet.

Indeed, I'll have to pass quietly by at least fifty nine other fine arrangements, for now, and that includes Paul Klipsch's resplendent three-channel systems, the CBS satellites, Fisher's new baby speakers - satellites too in that they are minus low bass - University dual-voice-coil woofers, Motorola Three-Channel, Aero Third Channel, "magnificent" Magnavoxes and all the rest.

I still must absorb, too, a monograph by Klipsch giving ten - count 'em, ten - ways to derive an electrical third channel from two stereo tracks. All quite fascinating, intriguing, confoosin' and the question is, where to begin. Where to end.

Well, I should say at once that, fascinating or no, I am as yet, practically speaking, unconvinced (nicht überzeugt) by any of these heady three-way possibilities and "it" is still ending where "it" began, with two fine speakers playing two tracks.

For listening, that is. I'm not persuaded - not yet - that a good stereo set-up needs any sort of enhancement (short of a three-track system straight through), whether to remove holes, widen the listening area, conserve cash or reduce bulk.

My stereo system remains basically two-piece and I revert to that arrangement - I have so far - after every excursion into three-way experiment.

Maybe I'm just lucky. My "stereo" is just fine, thank you. But ... you never can tell, and so while I continue to listen two-way, I continue, on the side, to experiment three-way. For it's always possible that there could be something better; I might be wrong.

And in addition, there is an extremely practical matter: if and supposing your stereo for any reason is unsatisfactory - and there are plenty of such situations - then isn't it possible that one or another of these ingenious three-point systems could make it better? Or make it cheaper, smaller, more convenient? A big question and nobody has the final answer.

Let's categorize. There are two general approaches (grundsätzliche Betrachtungsweisen) to this multiplying of the stereo output. They overlap by about 50%, but you can tell 'em apart, more or less. One line of thought involves a simplifying, space-saving, cost-cutting operation, that seeks to combine the bass end of both stereo channels into one outlet, on the theory that bass is not involved in the
stereo effect.

This leads to the satellite approach. Keep your highs properly separate, in two speakers, but remove the bass out of them (how far down?) and thereby make them much smaller and simpler. Two little speakers for the stereo, all the bass in one big woofer in the middle, or under the couch or any old place.

Some of the little speakers are semi-microscopic, implying that only the upper middle and the high frequencies are really of any use - also implying that all the rest can be safely put in the neutral middle. Others, more conservative and, I suspect, on sounder theoretical ground, simply shave off the bottom hundred-odd cycles of the full range, leaving everything from perhaps 150-200 cps upwards in the side speakers.

Good, because there is a remarkable gain in speaker simplicity here, at a relatively small loss in tonal range. A speaker that responds neatly down to 150 cps and up to the top can be astonishingly compact without serious compromise. As always, it's those last low cycles in the sub-cellar that make all the trouble for us, and always have since we started asking for them.

So, you see, there are quite fascinating possibilities in this first approach, the One-Woofer deal, provided you are really convinced that
(a) low bass really, practically, audibly, does come out non-directional and non-stereo; and provided
(b) that you have discovered an adequate way to combine the bass tones from the two stereo tracks into that one-woof middle.

Ah - what complications here! The mere fact that one company has put out a double-voice-coil woofer, combining the two tracks mechanically, and that another sends the traeks through a matrix and a complete third power "re-amplifier" shows that things aren't as simple as they seem.

The other approach (Betrachtungsweise) I will call, for symmetry, the Three-Tweet. The basic idea here is not to fuss with the base, but to spread out the top, redistributed into three equal channels. The bass may go along for the ride and probably will. It could even be one-woofer, and occasionally is.

But the interest, the ear-appeal, is in the three upper-end channels, two "regular" (left-right) and a third one in the middle. That interest is, of course, heightened by the fact that many a stereo recording, though two-channel in its commercial form, had three channels to begin with an includes direct center-channel information from separate mikes, just waiting - perhaps - to be reassembled into that middle channel.
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• Anmerkung : Als Ampex die erste 3 Kanal Bandmaschine vorgestellt hatte, wurden schon früh (1954) eine Menge 3-Kanal Stereoaufnahmen gemacht und archviert.

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This Three-Tweet way of thinking is quite democratic, for we find it in the Motorola beach portables (and more of the same), in Pilot stereo consoles and components, and we find it also in the relatively giant Klipsch three-way stereo systems, definitely not in the bargain basement.

(I haven't a doubt that these gentry feel themselves quite mutually exclusive and might well deny any similarity between their systems; but for my own categorizing purposes I lump all three as three-tweet threats.)

All in all, the general idea of three channels out of two has an exhileration about it that keeps it very much alive and isn't likely to let you rest in peace for long with your stuffy old two-speaker stereo.

The only trouble is, again, that the center channel poses some formidable complications in the unraveling, the derivation of one, convincing, natural, accurate sound out of removed parts of two other sounds, supposedly complete in themselves.

Redundancy, duplication, cancellation, confusion, all are serious dangers. Theory and practice must move hand in hand or, better, handcuff to handcuff. Sometimes they are - or seem to be - at diametric odds. Some people make their center channel from out-of-phase elements in the two main channels, for instance, elements that in theory ought to be everywhere but in the center - and the darned thing sounds quite reasonable in the listening, sometimes.

Differences that you'd think ought to be huge turn out to be trivial. Theoretically zany systems sound pretty good; theoretically correct arrangements just don't pan out. . . . Nope, it isn't easy, all this.
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Sometimes the best approach to clarity in this sort of area is not to make statements but to ask questions. There's nothing like a question, unanswered, to clear up the thinking process.

Therefore, before I deal briefly with something specific called Triophonic Stereo with Equalized Sound, I'll pose a few compound questions and toss in some tentative answers, here and there, as the spirit moves.

1. Does a center-channel (full-range) speaker help to widen the effective listening area in which spatial relationships are heard as reasonably natural?

Well, I dunno. I suspect that it does help in putting a close-up solo instrument in the center for people listening off towards the sides. It doesn't do a thing for the ends of the sound-spread and I doubt if it really helps the side listeners to hear the background center - the center of the orchestra in a symphony - in any truer relationship.

If a center channel is out of balance, or the speaker too far forward, it can do much more harm than good, destroying the illusion of space towards the rear that is produced by the cooperating outer speakers.
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2. What happens to the listening when the phase of the center components is juggled?

A+B, or A-B? Ideally, the center channel should contain the sum of the identical elements in the two channels - those sounds which ought to, and will appear automatically in the middle; what effect do you hear when instead of A+B, there is A-B in the central channel?

Does this "inside-out" condition, with the center speaker carrying elements that ought to be on the outer edges, sound as bad as it ought to?

Darn it, no. Sometimes I think that any old sound will do in the middle, so long as it's the same piece of music. Tentative reasoning - suggests strongly to me that most stereo sound is already so hashed up by room reflections and general acoustic confusion that the ear doesn't even notice a few discrepancies in the center area, unless called sharply to attention. We fool ourselves all the time, anyhow, - the idea is to do it with the best aesthetic effect and for the most pleasure.

Note well that stereo sound is far more positive in a dead listening situation than in live acoustics - though generally we rather like the reverberation of the live room. As mentioned last fall here, a really live room brings you no audible stereo whatsoever. Just a jumble, if a nice one.
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3. Is the rgihtness - or wrongness - of a central channel reproduction enhanced by three-track stereo originals (via two-track commercial stereo, of course) ?

That's a very interesting question with a theoretically answer that should be no, but probably isn't. The third-track stuff, in phase and identical on the two commercial channels, appears automatically in the middle in any good two-speaker stereo system, in phase.

If the speakers are reversed, it is thrown to the ends and all is chaos. Most people rather like this chaos - it's "stereo" to them, i.e. and exaggerated separation. Just like the dealer said.

In an ideal three-channel reproducing system the original third-track stuff should, in the same way, appear at the center speaker. In theory, it should sound exactly the same as with two speakers, at least from a central listening point. From the sides, as suggested previously, it should, maybe, have a slightly greater centralization.

But can you tell a two-track original from a three-track original on such a Three-Tweet system? Well, can you tell the difference on a standard system? I can - sometimes. Nevertheless, I can't help suspecting that a good three-way system will respond gracefully to a three-channel recording, restoring a good part of the original center segment to an independent, if a fused life. Fusion is taken for granted as essential in stereo. Lots of people don't like it.
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4. What if the phasing of the original third channel was out, or partly out, due to multimike mix-ups? Has happened, can happen.

Answer: utter confusion in the listening, and you can't do a thing about it. But you'll probably love the sound.

5. Does a center speaker and channel really full up the famous hole in the middle?

What hole? If there's a hole, maybe the record producer wanted it that way, so why fill it up? If your speakers are out of phase you'll get a fine hole, and you'll find that your guests will ooo and aah at the superb stereo separation.
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6. Can you get Fusion with a regular two-speaker set-up?

Sure. Just pick yourself two identical speakers with good high distribution forward (not up), find a medium-live living room and pick a symmetrical wall for the speakers, with conditions on both sides the same achitecturally, opposite right to left; set 'em at least five feet apart and maybe more, set yourself at the point of a rough equilateral triangle, choose a well-made stereo record ....

7. Is the bass in stereo music really nondirectional? Can it really come from any old place?

The lower you get, the less direction and less stereo effect there is - it doesn't just happen all of a sudden. Down at the bottom, bass is surely non-stereo, non-directional and the principle is clearly solid enough to put into practice in the One-Woof manner, as above.

But remember that bass music is full-range, that "bass" sounds, like a bass fiddle, are definitely directional because of the overtones present. Too many of us are casually confused on that.

To make a bass fiddle non-directional you must remove its very soul, its highs. If you can manage to extract only the bottom, from 200-or-so cps down, for your One-Woof speaker, you can let the fiddle's top overtones go out where they belong and the entire instrument will seem to be out there, bass and all.

But let the slightest trace of lower-middle sound get into your "Woof" speaker and it becomes a point source. Bad. Unless, of course, that's where the sound is supposed to be. Say, under the couch.

And with that, and with apologies to Weathers (ein Boxen-Hersteller) for lack of remaining space, I come to that company's tricky three-speaker system, two books and a box, that you'll see advertised as TrioPhonic.

It's not a three-channel system at all in the sense of my arguments above; it's a pure One-Woof, and so intended. The two side speakers are amazingly small, and the company has got them so they look like books, with rounded rear and a gold metal screen where the spine ought to be.

A big book, about the size of a small dictionary, and it contains a tricky cone speaker around nine inches long and two inches wide, damped by a piece of cottony stuff in front.

The frequency range of these little satellites is quite astonishing, ranging down into the very low hundreds of cycles and up to the top. They produce a lot of volume, too, with good efficiency, and you'll find it surprisingly hard to make them blast in overload.

Now maybe I'm running counter to the company's intentions, but I found these little book-speakers extremely useful as Two-channel playbacks, for portable stereo listening in great convenience and also for general stereo of surprisingly good over-all quality.

Yes, the bass was "thin" - i.e. missing at the bottom. But there was a lot more of it than in most portables, and the usual boorny, peaky bass quality was entirely absent. No doctoring for false bass.

I find that for a second system, easily installed or moved about, these two speakers are quite invaluable. Their tone is clear, the range wide, their slight tinniness is mainly, I think, an aural effect of the bass roll-off along with the wide-range highs. And so I recommend these Weathers midgets for your inspection as standard-type auxiliary stereo aids.

The TrioPhonic system, however, also includes a woofer, designed to produce only the very bottom and to be stuck behind or under something out of the way. The speaker is unusual in two respects, one being itself and the other the method of providing its signal.

The Hideaway woofer itself is flat, in a low, plain black box with larger overlapping top half that leaves a four-sided slot at the bottom for the emerging sound.

The speaker, I can say definitely, is very low in efficiency, taking more wallop by a good deal than the AR-type woofer with which I compared it.

The Weathers system, as above-mentioned, makes use of a small matrix arrangement that feeds from the 16-ohm speaker taps (Anschlüsse) of the two main amplifiers and combines the bass end (removing the highs) for re-feeding in A + B to a third power amplifier.

I am not up to investigating this tricky circuitry nor can I comment on its electrical properties, but I do feel, somehow, that this is a relatively complicated way to go about getting a good center signal.

Weathers has improved its idea by designing its own bass amplifier, a small transistor unit, to follow the summing circuit and feed the woofer. Good idea. I just used whatever I had around, and found the connecting-up rather a chore.

We tried the system out with on AR-2 woofer section (the tweeter disconnected) and the results were interesting. No question about it, the "One-Woof" principle works.

Standing off at a proper listening distance, I found that the bass was definitely present, definitely blended with the highs from the book-speakers, and definitely not directional. The AR could be put over on its back facing up, for an equally good blend of bass and treble.

I did find, though, that if the center woofer were moved forward too close to the listening spot, or if I jacked up the volume on the center speaker too high, things began to go wrong with the stereo illusion. The low bass is misleadingly faint to the ear and your first impulse is to turn it up much too far. Rightly balanced, it is scarcely audible by itself.

The complete TrioPhonic system was working overtime at last fall's Hi Fi Show and I must say it seemed to do a convincing job, on display there. The woofer in that show installation was on its side, rather than flat down on the floor. Maybe that lead weight works best sidewise.
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Two essential units in my home-style radio program set-up - along with my standard Ampex 350 - are items of incongruous home hi-fi equipment that have no business being there, so to speak, because they aren't supposed to be professional.

But the temporary "emergencies" that led to my plugging them into my circuit have now been extended into semi-permanency, since I really couldn't find a good reason for taking the units out again.

Both are Fisher units. One is the original Master Audio Control, the 80-C; it is my equalizer, for tailoring old and erratic tapes to present standards.
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• Anmerkung : Damit haben wir mindesten 3 Mono-Vorverstärker mit den diversen Entzerrerkurven für die verschiedensten Mono-Platten 78er und 33er gefunden.

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The other supplies another useful link, a variable cut-off filter, top and bottom: the Fisher Hi-Lo. It removes rumble and the like from the bottom up and is extremely useful in cutting down noise and distortion from the top downwards in the old 78 records I still occasionally broadcast. (I also can fuss with their "curves" via the Master Audio Control's tone controls.)

The little Hi-Lo unit was altered in only one important respect - we took out the main guts (Freßsäcke) in its low-end filter and now they dangle safely out of hum's way, on the end of an extension cable, for virtual silence in respect to induced noise.

I mention these simply as a prelude to stating that my latest batch of Fisher material, as of 'way back last June, shows every sign of being the same sort of orderly, good-looking, intelligently patterned and reliable equipment.

Let me tell you, the ultimate test in my home endurance race is staying-power. Any piece of hi-fi that I'm still using regularly after three or four years is good.

Stereo is here, now, and so I have the enlarged (but still compact) Fisher 400-C Stereophonic Master Audio Control (the lineal descendant of the 80-C) plus the SA-300 basic stereo amplifier, the big fellow in the line (30-30 watts).

The 400-CA. newer master control, is modified only in that it offers provision for separate tone control of each channel - which I do not need - plus some new facilities for remote control.

Well - Fisher is expecting soon to take back the Master Audio Control, et al, since I have the stuff on memo; but they're going to have a tough time getting it from me. I'm going to stall. With all due respect to many another excellent product (and I can't try 'em all) I can only state for the record that I continue to find Fisher's equipment reliable, easy to use, unusually good looking and good feeling; in fact the only immediate complaint I can dig up is petty - the little green signal lights on the pushbuttons on my units have blown, but this has been fixed on later production.

The stereo amplifier, SA-300, really needs no detailed accounting here. It just sits and works. No hum whatsoever - neither electical nor mechanical (from the transformers). Neat brushed-gold cage, a sensible, legible, simple arrangement of inputs and outputs with a handy level-set for each of the former. There's a special output with filter, to match electrostatic speakers to their woofers - an excellent way of being sure and definite, over and above the tone controls, as to a proper hook-up for this tricky type of tweeter.

The output balance-adjusting facilities are set up so that accidental confusion is unlikely; d.c. and hum balances for each channel are out of the way, under removable caps on the front panel. No more to be said except, again, the thing works and keeps working. I can't make a higher recommendation - and every day this report is delayed makes it better.

The 400-C Master Audio Control is basically like the original 80-C in outward set-up, but stereo has dictated important functional changes.

There is considerable simplification in non-essentials - only four pushbuttons, two auxiliary inputs, one with and one without level-set, where the old model had legions of level-sets right on the front panel.

OK by me - there's plenty of versatility left, and more room for the fingers. Two other switch positions - all of them dual, of course - cover phono-mike-tape and a tuner, one being "high-level" and the others involving the pair of preamplifiers.

Six neatly spaced knobs with thin gold bands at the edges take care of main functions, including tone. The left switch gives you two EIAA inputs (both via the "Phono" pushbutton) plus an "LP" equalization, presumably for old-type high-rise LP curves, and a 78 position - these being more or less standard.

Next in line are the outwardly standard balance control and two tone controls, with "flat" at the center position. (It was 11 years ago, wasn't it, that I was taking much space in AUDIO recommending this then-novel arrangement as desirable?) Volume and on-off come next, with loudness contour on a lever just above, and at the right end is the mode selector.

It's really gratifying, I should remark at this point, to see how quickly these basic stereo controls have settled down to more or less a standard outward format. It took many years longer for the equivalent in mono controls to reach a form as recognizeable, say, as the controls of the preautomatic automobile.

This is all to the good, as far as a widening market for stereo is concerned, for the biggest "occupational hazard" in stereo component selling is complexity.

Honestly (I say to my friends), the most recent crop of stereo control paneling displays hardly anything more complicated than the old mono controls - indeed, many are simpler. (For one thing, we no longer have 792 1/2 phono equalization positions).

Take courage! Stereo isn't really so complex, once common sense and ingenuity get to work on the problem.

It is in the details of the Fisher control unit that I find a few things to bring to your notice. Take 'em right to left. I haven't mentioned the left vertical lever switch (aesthetically matching the loudness lever on the right), which is none other than the "lo" half of my old friend, the Fisher Hi-Lo, a rumble filter from the bottom up at 20 (none), 50 and 100 cps cut-off, values that I feel are well chosen for practical use.

I like, too, the balance control (second knob from the left) which has values similar to those in the two tone controls involving a sort of well-bred moderation, with a relatively expanded "scale."

This balance control doesn't fade one channel entirely out at each end, but merely reduces it, building up the other, in a wide, slow taper. Good and sensible. Why go to extremes when the proper function of a balance control is to adjust, to modify ?

The wildest imaginable degree of unbalance isn't likely to be anywhere near the one-channel all-out vanishing point! Your balance control will never succeed in forcing a 90% week-kneed channel to match an 85% overloaded partner; so why bother.

The best balance control merely goes a little way, with a lot of knob-turn for free, flexible, easy operation and precise settings for exact future reference. That's Fisher - and probably other reputable makes too, though definitely not all.

Similarly, the Fisher tone controls have always struck me as admirably effective. I haven't even considered circuitry - I just use 'em. But again, they are noticeably moderate in extent, the extreme positions being well within a really usable, low-distortion range. Well-designed controls should always be that way, but I've tried many a hi-fi tone control with such exaggerated boost and rolloff that I hardly dared use more than a few degrees of knob-turn for fear of violent distortion.

It is this very feature, back in the old 80-C control unit, that allows me to use it for tape equalization in the copying. At the extreme high-end rolloff position, the old Fisher neatly equalizes an unintentional high boost that somehow managed to get into a large batch of my older Magnecorder tapes, in an effort we once made to match them to the then-different Ampex playback curve for broadcast.

On the air, these tapes squealed unmercifully and I winced, but could do nothing. (Eventually I bought an Ampex and that was that.) Now, after a run through this elderly home control unit and subsequent copying on the Ampex, the old tapes come out virtually flat and remarkably free from distortion.

Only an occasional overblown "sss" sibilant indicates what was once that unwanted boost in the top highs - and so I have modernized and saved for further use some hundreds of hours of the hardest work I ever did on tape. You can understand why I appreciate the simple virtues of a well-designed audio control unit.
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One final point. The right end of the Fisher stereo control is the more or less standard mode selector knob, with stereo, reverse stereo, channel A, channel B, and so on. But one unusual item on this Fisher knob had me quite bemused. Two positions are marked with admirably cockeyed mathemetical logic, "A+B" and "B+A."

Now that hit me at once as the acme of nonsense, for didn't we all learn in grade-school geometry or something, that when A equals B, then B equals A, AB is the same as BA, A added to B is the counterpart of B added to A ....

What? Was Avery Fisher (der Gründer und Chef von The Fisher)defying the axioms of mathematical self-evidency?

Well, I set out (without, of course, looking in the instruction book) to find what in heck those two positions might signify.

The intent is useful, if anticlimactic. All that happens is that one position feeds input A into both amplfiers, the other feeds input B into the same. Thus my FM radio zoomed out through both speakers on one position but there was silence on the other - no signal from that input.

It's a matter of nomenclature. After all, how are you going to say I love you in less than three words, not counting shorthand and Latin (te amo) f "Minnimm!" maybe?

Short of something like "CHANNEL A INPUT INTO BOTH AMPLIFIERS, I suppose "A+B" is as good as anything, though it still says nothing at all to me, next to "B+A". Just another example of an increasingly familiar problem often mentioned hereabouts - how to label complex audio functions in words of one letter, or maybe two.
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Whoops - I planned to talk about the AR-3 and I haven't left myself room. Everybody's had his say on that "Acoustic Research" speaker but me, and I've had a pair of them on hand since last June, thanks to the kindness of the company.

Well, I've said reams (lange Ggeschreibsel) about AR in the past, having been one of the very earliest AR enthusiasts. There really isn't much left for me to write now and, anyway, I'm scared to open my mouth; somebody might think I'm prejudiced, or hired by a Consumer Organization or something.

I'll only state then, that I have been using the two AR-3 units since last June for most of my listening and intend to continue using them indefinitely. That's for the record and it's enough.

Also for the record, I might add that I am still using my pair of KLH Six speakers, which I've had for almost two years, I guess.
If I think of anything else to say, I'll wait until there's more space. Nope - I haven't tried three AR-3s yet and don't intend to. See above!

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