The Audio Centennial (+1) Revolution

Despite the myriads of technological breakthroughs announced month after month with tedious regularity by manufacturers of pickups, amplifiers and loudspeakers, there are only five developments in the 101-year history of audio reproduction (footnote 1) that we would call truly revolutionary. We will doubtless offend many by stating that Edison's phonograph was not one of them. It was the starting point, it was not a turning point. Emile Berliner's disc was revolutionary, in that it changed the whole format of sound reproduction, and made possible true mass production of recordings (footnote 2).

Other revolutionary developments we would count would be: 2) Electrical recording and playback; 3) The long-playing record; 4) Tape recording; and 5) The stereo disc. We cannot count quadrasound because it has yet to revolutionize anything, nor do we include direct-to-disc recording because it is not new {all discs were direct prior to tape) and it is not likely to continue for long because of the next revolution, which is right around the corner. And what might that be? Digital recording is what (see Sidebar: "Pulse Code Modulation").

Digital or pulse-code-modulation reproduction can give an incredible 90–100dB S/N ratio, total freedom from speed variation and all the mechanical limitations of turntables and cartridges, distortion figures comparable to that of modern electronics (typically 1/10 that of the best conventional tape recorders), complete freedom from scrape flutter (footnote 3), and frequency response as smooth and almost as extended as a good power amplifier. And the hardware is here now. Pre-production prototypes have already been demonstrated by Sony, Mitsubishi, TEAC, 3-M/BBC, and two previously-unheard-of firms called Soundstream, Inc. (of Salt Lake City) and Tokyo Denka.

Some of the new PCM systems use the Philips-MCA disc system that was designed for video, others use digitally-encoded tape. Sony has already announced that they will be selling an adaptor that will allow their Betamax videocassette machines to function as digital audio recorders, and Mitsubishi has unveiled a digital-tape cassette recorder/player for the audiophile market—a cute little gadget about the same size as a Sony Betamax videocorder, the PCM-F1.

Whether any of the new systems will equal direct-to-disc quality remains to be seen. PCM tape recording will evidently eliminate all of the imperfections of analog tape, but it is more than likely that it will introduce a completely new set of as-yet-unimagincd imperfections of its own. But we won't have to wait five years to find out what's what about PCM. The hardware exists now, albeit in prototype form, and the manufacturers have learned that there is a large market out there for top-priced hardware that can promise better sound than ever before attainable. We'll hand you odds-on that we'll be able to buy PCM tape equipment within the next year!

But at what price? The 3M/BBC professional 32-channel PCM system will cost "under $150,000." Not even Mark Levinson would expect to sell that to audiophiles. Mitsubishi's pro recorder is expected to sell for circa $36,000—still a bit steep for any audiophile. But their cassette unit, aimed specifically at the audiophile market, will more than likely go for around $2000, and the anticipated price of Sony's Beta adapter will be around $800, buying you a fully operational digital recorder/player for around $2000—comparable to the price of a Revox A-700 analog recorder!

There is no question in our mind that, once the inevitable bugs in the first digital hardware have been exterminated, both the recording industry and the perfectionist audiophile field are going to embrace it with open wallets. Imagine a recorder small enough to carry under one arm that will deliver playback quality comparable to a direct-to-microphone connection! Who would ever again consider a 60-lb open-reel unit that must gobble tape at 15ips to produce tapes that are inferior in most ways to that cassette?

What recording studio would continue using an analog recorder when a PCM unit can give virtual direct-to-disc quality along with the ability to edit and do multiple copying without the slightest signal degradation, and without the need for using either high-headroom tapes or noise reduction? Who indeed!

The recent flurry of direct-to-disc recording is serving its purpose: It is proving even to the most pig-headed reactionaries at the major record companies that sound quality will sell records, as long as the sound is truly good rather than what the RCA and Columbia recording directors (or the musicians they have brainwashed) think of as "hi-fi." Sheffield Lab Records alone has racked up sales of almost 100,000 copies—at $12 a throw—of virtually every direct disc they have released, and rumor has it that the initial pressing order for their latest release (of the Los Angeles Philharmonic Orchestra) will be in the hundreds of thousands!

When was the last time an RCA or Columbia classical recording had an initial pressing order of even 100,000 copies? A typical symphonic recording is considered a commercial success if it sells 10,000 copies; rarely will a superstar performer like Van Cliburn bring in more than 40,000 US sales. Yet RCA and Columbia both turned us down flat when we suggested that, just as an experiment, they try putting out one no-holds-barred symphonic recording (and we offered, free, to help them do the job right.)

We would love to see the expression on those smug faces when they see Sheffield's sales figures for those upcoming Los Angeles Philharmonic recordings (which are simmply stupendous!) Sooner or later, both of those creaky old dinosaurs of the recording business will see the light, because to them it is hard, cold cash which illumes, and it must soon occur to them that good recordings make money. So they, too, will eventually discard their analog recorders and convert to PCM mastering, and when they find that that alone isn't enough to attract the sound-conscious buyer, they may even be forced to dismiss their creative record producers with the itchy fingers, toss out their 32-channel mixing consoles, and record with two strategically placed microphones the way grownups do these days. But they will never record direct to disc. That's a little too far out in left field for a massive, conservative record company, and it may not be necessary anyway if PCM recorders turn out to be as good as they probably, eventually, will.

Of course, the repercussions of a mass switch to PCM will be considerable. It will put an abrupt end to the manufacture of a wide variety of audiophile products which, like the buggy whip, will suddenly become irrelevant. All present disc-playing equipment and accessories will go, except for the few that are necessary to meet the demands of serious record collectors. Most of those collectors, except for the ones who value the object as much as its content, will probably copy all of their discs onto PCM tape and unload the originals at garage sales (probably minus their jackets, which will be kept for the notes and the pretty cover designs). Expensive open-reel tape recorders will become a glut on the market—hard to sell to perfectionists for 1/10 their original cost—as will the large-format (10½") reels of tape for them unless some of the digital machines can use them.

But now that the first flurry of raves about the recent PCM demonstrations are abating, we are beginning to hear reports that all is not as peachy-keen about digital sound as we had originally been led to believe. Bear in mind that, when the first PCM demos were held, the audiences were listening for all those analog tape problems that they knew all too well: The speed variations, the modulation hiss, the rounding-off of transients, and that subdued but ever-present background of hiss. They heard none of those problems at all, and came away proclaiming PCM to be the ultimate sound-recording system.

But some sharp-eared recordists who have worked with digital equipment soon started hearing other, quite unfamiliar anomalies in the sound—distortions for which there aren't as yet any descriptive terms. (We'll soon remedy that!) And lacking any convenient handles, those users could only report that the PCM recorders they had used made certain instruments sound "peculiar" or "mooshy" or "turned around." One recording engineer informed us that the extremely sharp ultrasonic filtering in a PCM unit he had worked with resulted in phase shift at lower audio frequencies amounting to 360°/octave. "Peculiar," indeed!

So while PCM is obviously destined to be the basis of the next hi-fi revolution, 100 years plus a couple after "Mary Had Her Little Lamb, it doesn't look as though it will come to us bearing in hand that Holy Grail of Ultimate Perfection. As the French like to say, with that expressive shrug of the shoulders, "The more things change, the more they stay the same." PCM will bring drastic changes in our approach to sound reproduction, and will in many ways represent a giant step closer to that Grail, but we won't be home free yet.

It was inevitable that digital audio, being so fundamentally different from the old familiar analog audio, would open an entirely new Pandora's Box of sonic flawdom. And naturally, if the first PCM devices are imperfect, it is also inevitable that some will be less imperfect than others. The pursuit of perfection will continue, much as it has until now. And as usual, it will be up to us picky perfectionists to guide the industry in the right direction, by purchasing the best PCM recorders and shunning the also-rans. So what else is new?

Ads: In or Out? Many moons ago, we opened our pages to dealer advertisements and, a while later, did likewise for manufacturers. Now we're not so sure it was such a hotsy-totsy idea.

Getting advertisers to meet deadlines has been more of a hassle than it's worth, and much of the subscriber mail on the subject has been negative. (Although few objected when we asked for reader reactions before we started taking ads.) So we are putting it to you again: Does the presence of ads in the magazine bother you? We'll do what most of you want, IF YOU'LL TELL US WHAT YOU WANT (footnote 4). Okay? Okay.—J. Gordon Holt



Footnote 1: Although Charles Cros, a French poet and amateur scientist, deposited a sealed envelope containing a summary of his ideas about a practical method of recording audio with photo-engraving with the French Academy of Sciences on April 30, 1877, the phonograph was invented in 1877 by Thomas Alva Edison. Edison's phonograph was the first to be able to both record and reproduce audio on a tinfoil sheet cylinder.—Ed

Footnote 2: It is impossible to mold an Edison-type cylinder recording without producing a pair of seams right across the grooved area. Duplicating was done by playing the original and re-recording it onto softened blank plastic cylinders. Multiple copies were made by duplicating from several once-removed copies. With a flat disc, moulding is possible because the stampers can be lifted out of the grooves that have just been impressed in the copy. The moulding seams are around the outer edge where they don't matter.—J. Gordon Holt

Footnote 3: Scrape flutter occurs to a greater or lesser degree on all tape recorders because tape is stretchable and there is always some friction between the head and the tape. The effect—which is also called "violining," for reasons which will become obvious—works like this: As the tape is drawn past the head by the transport, friction causes it to adhere to the head surface. The tape stretches slightly until the forward tension overcomes the friction, at which time the tape comes unstuck, slides forward to relieve the tension, then adheres to the head again. Thus, instead of a smooth motion past the head, the tape moves for™ ward in a series of very rapid stops and starts, just like the movement of a violin bow's hairs over a violin string. But unlike the violin's bow-hair action, which produces a fundamental-and-overtone motion of the string, tape violining usually occurs randomly, producing what sounds like a hiss riding on the signal modulations, and disappearing in the absence of any signal. It is, not surprisingly, called modulation hiss. Another effect of violining is to add a rough edge to the sound of high-frequency tones coming off the tape. PCM techniques eliminate all effects of scrape flutter on the sound.—J. Gordon Holt

Footnote 4: Following this informal reader poll in 1978, Stereophile continued to accept advertising, as it does to this day.—Ed

COMMENTS
Music_Guy's picture

Right on the mark with this one!

dalethorn's picture

37 years later, in the electronics business, and a good deal of what Holt envisioned hasn't been fully realized. Worst of all is the fact that the big record companies are taking advantage of the new technologies to make the recordings more commercial, and usually worse. But there are some good things - the elimination of the nth generation master for example, since bit-perfect copies can be made. This quote: "but it is more than likely that it will introduce a completely new set of as-yet-unimagined imperfections of its own" was true then, and we continue to discover new things. How long ago in that 37 years did we have jitter 100 percent fixed? 10 years ago? I don't think so.

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