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THE GATHERING of the Clan, the audio industry's June (1973) extravaganza otherwise known as CES (Consumer Electronics Show), provided once again, in just four days on Chicago's lakefront, a total picture of where high fidelity - and especially four-channel sound - is headed this fall (Herbst).

In outline, the picture is not far different from that drawn at the first "Winter CES" in January 73, an off-season mini version that accommodates visitors to Chicago's mammoth Housewares Show (reported in OFF DUTY in April 73 and May 73).

But much detail was filled in, since this time practically all industry members either trooped into the "McCormick Place exhibition hall" or arranged private showings of new lines at nearby hotels.

The razzle-dazzle exhibitionism of consumer hi-fi shows was only partly in evidence-few equipment demonstrations, for example, but numerous scantily clad models - since the purpose of CES is to attract dealers from around the country and distributors from abroad, rather than to draw the general public.

Crowds were scant, but sales managers with order books in hand had 'nary a complaint since business appeared to be good. The problem evident in the trade at last year's show - the acceptance of four-channel by dealers who mostly dislike boat-rocking controversy - appears solved.

Quadraphonic sound is no longer a will-we-or-won't-we matter, but one whose inevitability has won acceptance with all industry factions except the top fringe of Rolls-Royce class component makers - the same group that held out several years against stereo because of the prohibitive cost of doubling up on components in their stratospheric price range.

Surest sign that quadraphonic sound is with us for good is the series of G.E. commercials on Stateside TV, featuring Sammy Davis Jr. as four-channel salesman extraordinary (though, alas, he comes across the tube strictly in mono-phonic lo-fi).

Such investment in the new sound by industry "majors" insures that the public will demand the latest in home music at the local retail store. Dealers, like it or not, are ready. And manufacturers are thinking strictly four-channel, in its various forms, when planning new equipment.

The competitive demands of the marketplace demand that their technology keep pace. There are still plenty of stereo receivers coming on the market, but largely in the lower-price range since top-of-the-line engineering effort is in quadraphonics.

More and more, stereo new-product thinking is in terms of adaptability for four-channel. One can always add a rear-channel amplifier, for example, to complete the system later, and use an outboard decoder with the latest matrix and demodulator circuitry.

Next step up the four-channel ladder is the "strapped" four-channel receiver, which provides all necessary circuitry for discrete quadraphonics but doesn't require the immediate purchase of four loudspeakers. With a balanced, transformerless (BTL) power output stage, this unit permits doubling up the front and rear channels and connecting them to a single pair of speakers for conventional stereo with no waste of power. Two loudspeakers (and a flick of a switch) later, you have a full quad set-up.

The latest pack-it-with-everything receiver is, of course, quadraphonic all the way. It boasts the newest decoders and demodulators for SQ matrix, RM matrix and discrete CD-4.

All have been improved since last year, and refinements are continuing as designers work on new "chips" (ICs) that will sharply reduce per-unit cost when they go into mass production. We'll have more details on these in the second half of our CES report (Part II) next month.

Among the circuits due to appear in chip form is the CD-4 demodulator required for RCA's Quadradiscs, now hitting the market in increasing quantity and recently joined by the important WEA (Warner, Elektra and Atlantic) records group.

These discs also require a new-type cartridge, with wide-band response to pick up the 30 kHz carrier signal and a stylus tip especially designed to detect additional information in the record groove.

A year ago, cartridge manufacturers refused to be stampeded into tooling up for CD-4. Now they cautiously admit to being ready for an expected surge of discrete four-channel records and IC-type CD-4 demodulators by 1974.

The key to successful four-channel reproduced via CD-4 - once basic gear is installed - is proper adjustment of the demodulator's separation controls to match it to the cartridge.

Present techniques call for this adjustment to be done by ear, where a margin of error exists that can degrade front-rear separation by 10dB or more. Looking ahead, designers wonder whether this adjustment cannot eventually be coupled to the meters already built into most four-channel receivers. Thus the user could trim the separation control to a high degree of accuracy.

The fact that such refinements evolve, rather than just occur overnight, provides much of the continuing excitement in the home entertainment field.

And nowhere is this gradual evolution in technology more evident than in phonograph cartridges and record players.

The latter, too, advanced another step toward perfection at CES. The trend line here points to direct-drive turntables (no belts or idlers) with electronic speed control.

Makers of single-play machines continue to add automatic features, notably a hydraulic tone-arm lift at the end of the record, while the makers of top-of-the-line record changers strive so intently for state-of-the-art performance that some have even dropped the noise-producing changer mechanism altogether from selected premium-price automatic turntables.

It is in loudspeakers that a minor revolution appears in progress, since a handful of radical designs are catching on. Predictably, as the public's attention is drawn to one innovation or another, an army of camp-follower manufacturers rushes in to capitalize on the fallout.

Thus there is a new wave of odd-shaped boxes with multiple speakers bouncing sound off the walls. The slanted-back front panel with tweeters angled off to the sides for improved dispersion is another trend.

Even stronger is the move toward bulging grills, made possible by the development of reticulated (netlike) open-cell polyurethane foam that can be sculpted into acoustically transparent 3-dimensional shapes and painted to any color. They are not only stylish, but permit designers to experiment with sharply angled placement of tweeters under the grill, again in the interest of better dispersion than that achieved through a plain box with flat grill.

Speakers are also getting more expensive. This is due to the additional hardware required in multi-tweeter designs, and the growing shortage of lumber (Bauholz). So manufacturers are trying new materials for the box - expanded plastic in a few cases and vinyl "skins" in many models aimed at the medium-price field.

The economics of four-channel play an important role here, since the loudspeaker remains the most visible and furniture-like component in the system and, inherently, the quadraphonic installation means four of 'em.
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THE "LOGIC" IN 4-CHANNEL SOUND is still a subject for argument at industry gatherings such as Chicago's mammoth Consumer Electronics Show (CES). And by "logic" we mean not only the horse sense in producing and marketing quadraphonic systems, but also an important (and costly) part of the circuitry in the equipment.

By now it's clear to all concerned that quadraphonic sound requires four separate "discrete" channels of amplification, but what's still less than clear to many potential customers is the anatomy of the 4-channel circuits known variously as matrix decoders, demodulators and synthesizers.

Judging from our mail, many Off Duty readers are still confused as to

• 1) what they are,
• 2) which ones are needed and why, and especially
• 3) how to know a good one from a bad one.

So we'll tackle the questions in that order.
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All these extra circuits are, basically, substitutes for the real 4-channel that consists of four separate input signals. Work with four discrete channels on tape, either open-reel or Q-8 cartridge (or cassette 4-channel, introduced at the Chicago show) and you don't need any matrix substitute.

But when you opt for surround sound, chances are you want it for all your music, not just your latest tapes. You've get a collection of stereo tapes, maybe some favorites in mono.

There are thousands of stereo LPs around, and FM broadcasting will not go quadraphonic for a long time to come, so the owner of a 4-channel system requires a method of playing stereo-only signals through all four of his amplifiers.

A synthesizer is a circuit that "enhances" stereo by attempting to feed material to the rear speakers that is somewhat different from the sound heard in front. This simulated (phoney) 4-channel is achieved with phase tricks, reverb and other electronic gimmicks. Simon-pure it isn't, but it's handy to have.

The record people, too, want to give you four discrete signals, but they have to cram them into a tiny stereo-groove. Engineers tackling the problem are divided into two camps, and after a couple of years of squabbling they've agreed to disagree indefinitely.

It's now virtually a certainly that the two systems, matrix and Quadradisc, will coexist for years, at least until the FCC makes a determination as to the best method of broadcasting 4-channel sound.

The matrix QS and SQ disc is encoded, i.e. four discrete signals are scrambled according to a formula and reduced to a stereo pair, for purposes of cutting the record.

The Quadradisc, known as CD-4, modulates the rear channel information on a 30 kHz carrier frequency and superimposes it on the stereo signal in the groove.

To play a matrixed record you need a decoder. - For CD-4 you need a demodulator.

The complete 4-channel installation requires both, since records of both types are hitting the market in increasing quantity.

Since every manufacturer of 4-channel equipment offers one or more of the above, we come now to the gut issue - which one is "best" ?

And here practically everybody - manufacturer, dealer and customer alike - is caught in a technological squeeze play. Because the best units in the laboratory are still mighty expensive to produce for home consumption.

Each system's backers can put on a superb 4-channel demonstration that will instantly convince the listener of its superiority. But putting the same quality decoder or demodulator into your home at a competitive price is another matter, because it involves sophisticated new circuitry requiring dozens of transistors.

Remember, too, that a high-fidelity music system is only as good as its weakest link, and the advanced tuners and amplifiers now available at modest prices pose an enormous challenge to the designer of elaborate 4-channel circuitry.

It's relatively easy to produce an adequate decoder or demodulator for cheap "package" systems because the higher distortion level will "mask" whatever deficiencies turn up. But the owner of high performance equipment, with distortion of about 0.1 per cent, will quickly hear the difference.

He won't be satisfied with decoders that pump and whistle on complicated passages or demodulators that burp on encountering a speck of dust. Few of these finnicky customers, however, are prepared to pay upwards of $250 for an accessory decoder.

While the production people wrestle with this dilemma, engineers in the lab are having a ball developing 4-channel technology. All the systems are significantly better than they were a year ago.
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The matrix clan is still divided between CBS' SQ and Sansui's QS, the latter adopted as standard in Japan and bearing the generic name RM for "Regular Matrix".

The CBS system can also be called "phase matrix." The reason for these generic names, by the way, is that manufacturers have had to bury the hatchet and, no matter how partisan they are to their particular system, agree to include the other guy's system in their hardware.

Thus, although Sony (tied in with CBS Japan) would probably never consider putting the letters QS alongside its own SQ on the front panel of a receiver, it might go along with RM.

And Sansui, too, must provide its customers the capability of playing SQ discs, but can't use CBS's proprietary name, so it calls the other system "phase matrix".

The difference between these two matrix systems is a subtle one. Both claim that their latest decoders deliver a "square" sound field, i.e. full separation (20dB or better) between left-right and front-rear speakers, and they have the technical papers (presented to their peers at AES "Audio Engineering Society" meetings) to prove it.

Each claims its formula for matrixing is superior and lobbies mightily with broadcasters and record companies so they'll favor one over the other.

Sansui has supplied numerous FM stations with its elaborate QSE-4 encoder. The system is widely used Stateside since matrixing is now the only method of quadraphonic broadcasting that will not incur the wrath of the FCC (several systems for discrete 4-channel transmission are up for consideration but none has been authorized).

CBS has lagged in getting encoders into the hands of radio stations, but its Columbia Records Division has gone SQ in a big way, giving this matrix enormous clout in the marketplace. So there is little choice for manufacturers of hardware other than to include both types of decoder in latest models.

The manufacturers' dilemma, however, is not whether to include the decoder, but rather how much of this costly circuitry can reasonably be built into production-model receivers at this stage of development.

The "square" 4-channel sound field is achieved by means of "logic" circuitry requiring numerous transistors. To match the superb performance of laboratory models, the circuits must operate over a broad range of frequencies and be effective between front and rear channels as well as left and right.

But neither Sansui nor CBS-Sony can afford to include that much costly circuitry into a 4-channel receiver, and neither can other manufacturers because the equipment would be priced out of sight. So the decoders in today's production models are necessarily a compromise on the "best" 4-channel circuitry thus far devised.

But there were encouraging signs, at the big Consumer Electronics Show in Chicago, that equipment on sale this fall would boast new-generation Integrated Circuits with full-logic capability and performance more akin to that attained by engineers in the lab. The new IC "chips" on the way will drastically reduce per-unit cost for all systems - SQ, QS and CD-4.
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Es geht weiter mit Teil 3
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TO COMPLETE A REPORT on a giant audio trade exhibition such as CES (Consumer Electronics Show) at McCormick Place on Chicago's lakefront, a visitor needs comfortable shoes, an ample supply of shopping bags to haul pounds of literature and, if you will, a strong stomach.

Because, when dozens of manufacturers with similar product lines churn out hundreds of press releases, the intrepid reporter whose job is to read and interpret them all is subjected to the same old bromides, over and over ad nauseam.

Manufacturer "A", for example, has a series of "step-down models" that "contains features normally found only in much higher priced models". But, so does manufacturer "B", "C" and so on. And rare indeed is the "exclusive" feature, often an exciting new circuit, that hasn't worn pretty thin after turning up in press releases issued simultaneously by a dozen different companies.

But sometimes there is pure joy even in repetition of worn-out phraseology. Especially the specifications that describe the new amplifiers. After years of playing the numbers game, striving for ever-higher power ratings at the expense of believability, the audio trade has finally adopted as its yardstick the conservative rms rating that gives real weight to power specifications.

Since the new, more stringent specs do far more to tell customers what they're getting than reams of press-agent verbiage, it's actually fun to read them, over and over. The new language of amplifier specifications is a little like old German wine labels - the longer it reads, the more true information it contains, generally.

"Fifty watts (rms) per channel," for example, is a whole lot better than the old "150 watts music power." But "50 watts (rms) per channel, both channels driven" is still better. Then there's "50 watts (rms) per channel, both channels driven with THD not exeeding 0.5 per cent," which goes one better.

But true happiness is a spec that reads, "50 watts (rms) per channel, both channels driven from 20 to 20,000 Hz with THD not exceeding 0.5 per cent." Then you really know that the manufacturer is arriving at the 50-watt rating in a most conservative way.

And you have a basis of comparison with other amplifiers rated the same way. One manufacturer may shoot for more power -- say 60 watts with no increase in harmonic distortion throughout the same bandwidth - while another aims to achieve the 50-watt rating at still lower THD of, say, 0.3 per cent, or through a still broader range of frequencies.

So, while we've tried to spare you the adman's verbal padding in this CES report, you'll find amplifier specifications included in all their verbose glory. It was a long time coming and stands repeating.
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Aufgrund der der großen Anzahl der deutlich größeren Juni 1973er Firmen- und Produkt- informationen ist dieser Produkt-Teil auf eine eigene Seite ausgelagert.
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