by Edward Tatnall Canby
Years back when this magazine was adolescent and I used to make up my own zany titles, I occasionally resorted to a sort of catch-all phrase that keeps ringing in my head. Obviously, it originated in the Italian-American community: DIS'A AND DATA. Or was it out of somebody like the Schnozzola Durante? Credit where credit is due. A good rhythm, a give-and-a-take --like to and fro, here and there, back and forth, up and down, His & Hers, take it or leave it. DIS'A AND DATA! I can hear its sonic ambience so nicely--say in a certain passage out of the Berlioz Fantastic Symphony, which you may locate for yourself if you can. But on paper the most interesting sort of dis'a and data is the kind of back-and-forth exchange that the rhythm implies--out of our far-flung correspondents. (Just got a recording from Singapore and a super-8 sound film from Hong Kong, for which I have no projector.) There's only one reason why our energetic correspondents don't appear in all our departments regularly every month for a really lively exchange of ideas--it takes SO long.
You can talk to a sourdough or an Eskimo in Alaska for pennies by phone, and we can pour water out of a bottle on Mars. But a three-minute (reading time) exchange via magazine is like a phone call to Mars. You ring up and ask, hey, how's the weather up there? And more than half an hour later at the speed of light you hear, fine, but the smog is sort of red. It takes even longer in a terrestrial exchange of words via magazine. It's grotesque.
What with the initial transportation via pony express (courtesy of the Postal Service), the accumulation in the Off ice Memory Bank (a file folder), the re-forwardation to the ultimate destination (me), and then the answeration, back by snail express to the Edi tor, and the copy reader, and the printer, and the distributor, and eventually, all in due time, to YOU. One can grow old answering correspondence and one often does.
So hail, all you Rip Van Winkles, glad to welcome you aboard. For instance, there is (was) Brian Berkeley, a (then) senior in EE at MIT and author of one of the most genially and totally unintelligible papers presented last autumn at the AES (that is, unintelligible for me --I haven't really learned the digital lingo yet), called "A Floating-Point Digitally Transcribed High-Fidelity Audio Mixing System." Phew! (But I do get hic essential point or purpose, which is to begin that rather painful process of intermediate digital conversion as applied to the many and degrading steps in the audio chain that now must come between a digital original recording and a finished commercial record.) Lo--Mr. Berkeley can also write English, a language that I am often able to comprehend, and he wrote me a few millennia ago to remark on my "digital" column of February, 1978, pointing out one rather import ant technical error I had made, inadvertently, in my enthusiasm for the astonishing new parameters of digital recording.
Misunderstood Hyperbole
Thank the Lord, the man liked my piece, and commended me for waving the digital flag, as he put it. But, he said, "I was somewhat disturbed when I read 'signal to noise at virtual infinity-- there is no noise; 90 dB is the acceptable figure. "Now that phrase of mine, you understand, was mere English hyper bole, not intended as a precise engineering description. I should have said, even so, that in practical terms, in effect, as the listener listens, there is no noise. If noise is measured as 90 dB down by any system I know of, then it is really not a noticeable interference to the basic audio signal! Yet Mr. Berkeley was right just the same, and a conscientious engineer and thinker.
What amazed me was that not another one of our readers in all their thousands picked me up on this basic point--for it is that. Let me continue with the Berkeley letter, which applies precisely as well today as it did when written.
"There is noise! In a fixed-point representation, the noise is equal to the last significant bit, simply because the signal is not specified to any better resolution. In a floating-point system, things are a little different, but certainly, again, you can't get infinite S/N ratio (i.e. no noise) without having an infinite number of bits in the mantissa.
"At any rate, to achieve a S/N ratio of 90 dB (and essentially a dynamic range of 90 dB), one must use a representation scheme at least 15 bits wide with a fixed-point system, motivating a floating-point scheme. The problem with such a wide representation is that conversion devices (A/Ds and D/As) fast enough to do the job are too ex pensive to be practical (presently) for home or professional use."
Correct Rhetoric
At that point I will allow you engineering experts to carry on --I stand corrected on the essential point, which is that one must not use casual infinities like NO noise when such phrases, even rhetorically, are in fact technically inaccurate. I am sorry to have observed, in this connection, that in fact a number of the new and sensational digital products are described just this way --perhaps in some cases technically accurate, in other cases surely not. Described not by me, nor my writing colleagues, but by the promoters themselves. How about, for instance, "Print-through: NONE." I suspect that it might take a lot of our readers a few moments of thought to decide whether that one is technically allowable from a strict engineering viewpoint.
Why else do you suppose that many writers take to using weasel words, to avoid trouble (rightly)? So-and-so travel offer is possibly the finest bar gain ever to be made available. That new Broadway play is perhaps the greatest play in the last 25 1/2 years. Our magazine is virtually the only one that prints good equipment reviews.
(Ugh--please not that. Because it is possibly not the truth.) I admit to using these terms and similar, once in awhile, if only because I also display a varying amount of noise in my own signal and I try, always, to define that noise element as accurately as I can, opening up or closing down my parameters to fit each case. Horse laughs from you who merely read, and do not write! But the essence of good writing remains in every area to fit your words, your terms, as closely as possible to the case in hand.
Not having done a study, I cannot say that 59 percent of our readers do not know how to spell. Nor could I say that only a few of them are bad spellers. Without the slightest doubt, some of them, quite a number of them, maybe even many of them, even very many of them, are poor spellers. I have much evidence before my very eyes. It exists! There is spelling noise in our readership signal.
Dare you deny it? But which words would you use to describe same? For instance, friend Berkeley, in his latest letter of long-distance, time-delayed follow-up, has proposed a new term that I had not seen before in my craft as a writer. I like it. Volumn! Now that may be a digital term, for all I know, like another he uses, namely two's. Volumn is like column and I suppose that the adjective, columnar in one case, must be volumnar in the other. Or maybe volumnious? What I cannot tell you is how to pronounce this new digital term. Should we say "vol-yoom" (and so, of course, col yoom) --or is it vollum and collum? I wouldn't know. Brian Berkeley, if you wish to short circuit the time delay, may now be reached at Carnegie-Mellon University, Dept. of Electrical Engineering, Schenley Park, Pittsburgh, PA 15213.
Let's round this out with another error exchange, time-lagged as usual.
You may remember, back a few infinities, that I got myself all fired up over the terminology used in European languages for the common hi-fi equipment items --and ended up with the thought that the word deck was a good one and might be extended by us, as it has been in other languages than ours. Milford S. Brown of El Cerrito, CA, promptly picked me up on this point and he is still right, if the problem is not exactly earth shaking.
Scientific Semantics
Instead of a "turntable," I had thought, why not a record deck. I was talking about the reissued AR manual unit, then and now on the market as a basic device for producing sound from the LP (and 45) disc. If your hi-fi sys tem makes use of a tape deck, then why not a record deck? Well, a good reason, as Mr. Brown makes clear. A tape deck is a more complex machine in some respects than a record playing unit, for it includes a preamplifier, equalized to tape-playback parameters. The record player depends on a preamp built into your --uh, let's see, what shall I call it? You know what I mean. A record deck, then, should rightly include a built-in preamp for its phono cartridge, if it is to be comparable to a tape deck. But, like the tape deck, no power amplifiers.
"A record deck seems like a good idea (says Mr. Brown) because it minimizes the distance between the low level output of the cartridge and the first stages of amplification. In addition, all of the decks in the system could be connected to a switching-volume-tone-etc. unit, which could either be separate from or combined with the power amplifier. Or even better, do away with the power amp as a separate chassis (the box in/on which the bits and pieces are assembled) and put one in each speaker enclosure ... This complete separation would avoid the cross-channel interaction of a common power supply, and the room that contained the (equipment) would look less cluttered." Well, I was mainly talking semantics; I thought that receiver was a fuzzily inaccurate term as compared to the alternative tuner, and still think so.
Table goes off at still another slant, semantically, and I offered the deck alternative as a useful beginning to wards better and more consistent names for the things we make and sell.
Again, I stand corrected. So let's have record decks with built-in preamps.
It is quite possible that in due time this may indeed become a new and standard arrangement and for good reasons. I think it would help to simplify the present horrendous complexities of internal switching and external cabling that still clutter our, er, whatever-you-callems. You wouldn't have to switcha preamp built into a record deck. It would just be there and act automatically, like the equalized preamp in the tape deck. Though I suppose for awhile a switch would be needed, in case you preferred to use an external preamp as at present, the one built into the next chassis in line.
Well, one thing I know. The semantic demise of the old term chassis for what is now called a receiver was a move in the right direction. Mr. Brown would agree. That was decking the fi with boughs of folly.
(Audio magazine, May 1979; Edward Tatnall Canby )
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