Digital. It has become the buzzword of the decade in home entertainment technology. Digital recording represents the greatest single leap in quality of reproduction since Edison invented the phonograph, bringing home pure, undistorted sound at prices even the most casual music fan can afford.
You`ll also find ”digital” plastered all over other kinds of new consumer technology, from stereo gear to VCRs and televisions. It has become a new mark of quality, but sometimes the word ends up meaning many different things to many different people.
Strictly speaking, digital recording means that sound has been translated into zeros and ones, the two numbers that computers understand and operate on. In this form, the information is of the same sort as the data stored on a personal computer`s floppy disk. When the sound is played back, high-speed electronic circuits reconvert these patterns of numbers to their original form. The most familiar example of this, today, is the compact audio disc, the CD.
Why digital? Conventional tapes and phonograph records have, for decades, fought a battle against noise. Noise tends to build up while a record is being produced, multiplying in the recording, mixing and editing process. Tape hiss and surface noise are present–and audible–in even the best tapes and records you can buy.
This is because in ”analog” recording, no distinction is made between the sound being recorded and the background noise of the medium that is capturing it. The two are forever wedded, and when a record ”wears out” the noise eventually wins.
Since digital sound is expressed as a stream of millions of numbers that don`t change from copy to copy, the compact disc you buy in a store sounds exactly as the music did in the recording studio. And it will always sound as good–for dozens and dozens of years, perhaps–as long as the equipment you are playing it on is able to read those numbers accurately.
The bad news for consumers who have become familiar with this idea is that the ”digital” label doesn`t always assure this same, high-quality approach to audio or video.
AUDIO
The rage in consumer audio is, of course, the compact disc (CD), the little silver records that play music with almost unerring and astonishing accuracy. The CD is a true digital medium.
(Not everyone ultimately agrees on the CD`s claim to quality. CD`s are noise-free, but some audio critics, contending that the sound can be harsh and abrasive, still tout the merits of the analog LP. The debate is likely to continue, too.)
The music on some CDs did not begin life as purely digital sound. Analog recording is still the predominant method of record production, even in large commercial studios, and these records often have more background noise, more limited tonal range and more distortion than purely digital recordings.
Most older, pre-CD albums, from legendary classical recordings to pop favorites and jazz standards, were of course recorded before the advent of digital recording systems. To be issued on compact disc, they must be
”digitally remastered,” or digitally re-recorded. The original analog recording is transferred to digital tape or disc by recording from the best available analog copy, usually the original studio master tapes.
To confuse matters, some of these new digitally remastered versions are being issued as non-digital, black-plastic LPs, as well as CDs. Does this mean that the old-fashioned LP is suddenly a digital record? No, although the sound from these digitally remastered LPs is sometimes better than the originally released version. At times, though, the digital remastering only results in a harsh, unnatural sound that will be unpleasant to the listener who is very familiar with the older recording.
Because of this, consumers have no way of telling whether new ”digital” versions of their favorites actually sound better, other than listening to them. Digital is a mixed blessing.
As for compact disc versions of older albums, when the digital remastering is done with skill and taste (as it is on quite a few CD reissues of older Verve jazz discs and some of the newly issued Motown CDs), listening to these albums is like hearing them for the first time. When it is done haphazardly (lots of off-label CD compilations of 1950s rock, for example), the result can be disastrous–full of hiss and distortion.
The best way to determine the technical lineage of a recording is to look for a standard three-letter code, somewhere on the jacket. This code is most often used on CDs, though not all record labels have yet chosen to adopt it. In this so-called ”SPARS Code,” each of the three letters is always either
”D” or ”A,” for digital or analog. The first letter indicates the original method of recording and the second is the method of mixing or remastering. The last letter stands for the medium, itself. For CDs, the last letter will always be ”D” because the compact disc is a purely digital medium. The two most common designations are ”DDD” (digitally recorded and mixed) and ”ADD” (an older, analog recording that`s digitally remastered).
Now, a new digital sound medium, digital audio tape (DAT), a close relative to the CD, is commercially just around the corner. Several manufacturers, including Sony, showed prototypes of DAT cassette recorders at recent electronics shows in the U.S. and Japan. These function just like home audio cassette recorders, but are purely digital machines that use a tiny tape cassette and a set of spinning magnetic heads similar to those in VCRs.
The technical specifications of DAT recorders are actually better than those of CD players, although only well-trained ears may be able to tell the difference. And this quality doesn`t come cheap. Pioneering consumers will pay up to $1,500 for the first generation of machines and $10 to $20 per 2-hour blank tape. Prices are certain to tumble, however, in the next few years.
VIDEO
Here`s where the real digital hucksterism is going on, in visual media.
Just as it is possible to digitally record sound, there is digital video. The picture portion of a television signal is converted to numbers and is reproduced with the same kind of impressive quality. Pure digital video has superb color and none of the ”snow” or visual noise associated with conventional, analog television.
Digital video is real. But not, as you may be led to believe by claims for new VCRs, at the consumer level. Manufacturers have stuck a ”digital”
label on many of this year`s VCR models to sell several new ”bells and whistles.” Their motive is, naturally, to capitalize on the perception of quality caused by the success of the CD. The consumer thinks ”Gee, if my CD player sounds so good, maybe a digital VCR will look great!” Think again.
In fact, a truly digital VCR would be incompatible with all present home video formats, VHS, Beta and 8 mm.
This all started more than a year ago, when Japanese manufacturer Toshiba showed its first VHS ”digital” VCR, one that stored a picture in memory chips to offer a rock-steady still frame (in the recorder`s ”pause” mode)
and clear, stable slow-motion. It didn`t use digital techniques to actually record the TV signals, but Toshiba thought it justified a ”digital” label anyway.
One of Toshiba`s competitors, Hitachi, which builds VCRs for RCA and others to sell in the United States, went a step further. Hitachi added features like ”picture-in-picture” (a second, smaller picture from another channel in one corner of the screen), as well as non-essential special effects like ”posterization” and other oddball picture effects, to their VCRs. Again, it was ”digital” that got the hype. So far, though, there was no digital recording.
Finally, NEC (Nippon Electric Corporation, known as the ”IBM of Japan”
for their heavy involvement in computers) issued its own digital VCR, which finally did offer an improvement in video quality. NEC claims to improve the picture quality by comparing digital samples of the video signal and reducing the visual ”noise” by sophisticated computer techniques. Yet, the quality gained in the pictures from NEC`s digital VCRs doesn`t compare with the kind of dramatic improvement that CD audio offers. Instead, NEC`s digital VCRs only produce somewhat cleaner-looking VHS signals on playback.
True digital video recorders are a long way from appearing at the consumer level–years, maybe a decade away.
(Japanese VCR manufacturers just announced a new home video format, Super VHS or S-VHS, that could postpone purely digital consumer video gear even longer. S-VHS machines, which will appear in Japan this summer, are not
”digital” VCRs, but could offer picture quality comparable to professional broadcast equipment. They are expected to cost $200 to $300 more than present VHS models.)
TO THE FUTURE
Several years ago, Japanese engineers developed an entirely new way to record the audio portion of a videocassette. This technique has come to be known as ”Hi-Fi,” and both VHS Hi-Fi and Beta Hi-Fi recorders sound great, almost as good as a compact disc. From a technical standpoint, though, this is not digital recording.
But when Sony introduced their new 8 mm. video recorders, they designed a way to put real digital sound on tape, along with a picture. Sony has also introduced 8 mm. VCRs that double as digital audio-only recorders. On some models, in an audio-only mode, you can record 24 hours of digital sound on a single 8mm videocassette. Although this is real digital recording, the quality of 8 mm. digital audio does not match either the compact disc or the forthcoming DAT recorders mentioned above. And although the recordings are comparatively noise-free, tonal range is limited.
On a recently introduced ”digital” VHS video recorder, the DX-900 model, Toshiba has included its own digital audio-only recording scheme. You are limited to 6 hours of audio on a single (standard length) VHS cassette, but the quality is closer to the compact disc sound. Again, the new DAT recorders are slightly better.
Pioneer, another Japanese manufacturer, offers the ultimate video/audio player. Pioneer is the main promoter of the laser videodisc, a twelve-inch video and audio disc that is the ”big brother” of the CD. Not only will the Pioneer CLD-909 play both compact discs and two-hour videodiscs, but the company (which also produces the discs, themselves) is encoding many of its videodiscs with digital soundtracks that sound every bit as good as CDs.
Further down the road are two potentially interesting developments, CD-ROM and CD-I. A CD-ROM (for Compact Disc, Read-Only Memory) is a compact disc devoted to storing computer information, rather than sound. Each CD is capable of storing about 600 million characters of information, or about 1,000 average-length books. When a personal computer`s floppy disk drive is replaced with a CD-ROM player, the information can be searched, sorted and read on the computer`s screen. This opens tremendous opportunities for delivering written matter, especially reference materials.
CD-ROMs have been slow to emerge, though, in part because of the promise of something called CD-I, for Compact Disc, Interactive.
CD-I is aimed squarely at the consumer market. It is a scheme for combining many kinds of information–from computer data, to sound to full-motion video–on a standard CD. The CD-I proponents have touted the medium as a kind of ”living book” with words, full-color video still pictures, speech, music and short motion sequences. In effect, it would merge all present home entertainment and information technologies, and the players would be the kind of machines that home computers never were.
Still, even prototype CD-I players have not yet shown up at major international electronics events and industry observers think they are at least a year away, if not more, from becoming a reality. Major players though –Sony, Apple Computer, National Geographic, Warner Brothers` Records and even George Lucas` Lucasfilms production company–are already involved in this new medium.
CAVEAT EMPTOR
A few words of caution for those cruising the technological landscape:
Long before the recent announcements of DAT recorders, the ”digital”
label had found its way onto ordinary blank audio cassettes–the kind you now use in your car or Walkman–as a kind of marketing gimmick. Here, the designation is meant to indicate that these tapes are better for making copies of CDs, at best an arguable claim.
Don`t, however, be fooled into thinking that you`re getting the new DAT technology in a new brand of $2.49 audio cassette. You`re not.
As for stereo hardware, the ”digital” label does not mean that digital recording technology is always being employed. There are no such things as digital headphones, for example, not even Sony`s expensive phones aimed at CD fans. The word, as applied here, is strictly another marketing ploy, meant to suggest the headsets can match the quality demands of listening to CDs. Nor are there real digital speakers or microphones. On some receivers (amplifiers with built-in radios), the ”digital” label only means that the radio tuning section uses microchips instead of knobs.
For years, television set manufacturers have promised that digital TV sets were going to revolutionize the quality of the picture we see in our living rooms. Digital TVs would eliminate problems of distortion, ghosts and
”snow,” and would combine several different pictures on the screen at one time. All this would be accomplished by breaking down the video signals into numbers that computer circuitry could then work its wonders on.
After the introduction of only a handful of (expensive) fully digital TVs, the stampede of buyers anxious to trade their old TV sets in for this year`s model hasn`t materialized, much to the consternation of set
manufacturers. In fact, most digital TVs don`t offer an improvement in picture quality, only a few gimmicks such as ”picture-in-picture” (PIP). This may be useful for sports fans caught between seasons, but it isn`t something that even avid TV viewers can`t live without.
One good rule of thumb is to be keenly skeptical of the ”digital” label on consumer hardware. Ask questions and don`t be satisfied with vague answers. Is it really digital? Or is it only a gimmick?
