Editor's Review (Sept. 1974)

THE CONSUMER Electronics Show was held in Chicago's McCormick Place again this June, and broke all previous records in number of attendees, exhibitors, and space used, according to the Electronics Industries Assn. which sponsors the semiannual event. The basic trend, if trend there was, was toward higher quality products-both in the "no compromise" category and in the "dollars versus features" group from which most of us must purchase our systems. A good many of the new products might well have been predicted before the show, in that they were logical advances of existing technology, rather than revolutionary scientific breakthroughs. One example of this is that many of the new four-channel receivers had all three quadraphonic systems, rather than just one as most did last year. Logical but not revolutionary. Two-channel receivers generally had more power, more flexible tape and speaker facilities, tuner sections with less distortion and greater separation, and overall appeared to be somewhat better bargains than in years past. Logical advances, but not revolutionary.

Speakers too were predictable-with better, more controllable tweeters and of larger size for fewer accompanying design compromises in bass response.

There was a stack of front-loading cassette decks, which require less room in an audio installation as you can put an amp or tuner right on top of one. The features of these decks, while a far cry from what was even dreamed of a few years ago, were almost standard in that one could find the same fine features at almost every maker's booth. While I wouldn't want a cassette deck without good transport control, Dolby NR, extended frequency response, switchable bias and EQ, etc., these features are no longer revolutionary and their insertion into decks across the board is simply logical. How far cassettes have come! (Footnote here: Several decks now have a third head for monitoring.) Open-reel (O-R) decks are looking better and better too, with more sophisticated logic, syncing, and many with 15 ips as top speed. O-R decks have benefited greatly from the new and better transports; with some units you can literally play the Minute Waltz on the speed/direction buttons and not wind up with polyester confetti. But again these are logical advances, rather than startling breakthroughs.

Several products do rate a special mention for true design breakthroughs, however. Three firms are reported to have FET power amps: Yamaha, Kenwood, and Sony Corporation. These are apparently beyond the prototype stage now, though not yet ready for final release to the buying public. (Incidentally, I recently had a brief preview of the Yamaha version, and if what I heard was any indication, these new amps have extraordinary listening qualities.) Dick Sequerra has finally stopped making his tuner better, and we were very pleased to be able to publish a test report on it last month. There were some hot new tape formulations from 3M (Classic in all three formats), Superscope (Ferri-chrome in cassette only, which is said to be quite similar to the 3M cassette offering, while the 3M O-R and cartridge formulations are not dual layer), Capitol (The Music Tape in all three formats), TDK (Audua in open reel), BASF (LH Super in cassette), and Nakamichi (EK in cassette, to be available shortly). There were a couple of new spin-outs in the turntable race; B&O and Philips showed units with rather sophisticated logic-control mechanisms, while BIC displayed two American-made belt-drive, multi-play units. Philips was also demonstrating their new motional-feedback speaker system, while Leslie held forth with their new DVX system, which is the subject of an article by Ben Bauer this month. All in all, a pleasing show.

FCC Approves Dolby FM-Casts FM stations are now free to use a combination of Dolby B-Type nose reduction and reduced pre-emphasis (25 µ S, instead of 75 µ S), says the Federal Communications Commission, without application or notification to the Commission. Such a change in pre emphasis (the amount by which high frequencies are boosted during broadcast) lowers the possibility of overmodulation, but would also lower high frequency response of present FM tuners, resulting in a subdued sound. Reception of a Dolby B-type encoded FM signal without decoding results in a signal with boosted high frequencies. A combination of the two, however, results in relatively flat signal, and listeners with conventional equipment should benefit by a reduction of high-frequency distortion and/or higher program level.

The greatest benefits, however, go to those listeners with a 25-µS de-emphasis tuner and a Dolby B type unit: better S/ N, greater dynamic range even at high frequencies, better reception in fringe and weak signal areas, and reduced possibility of interference.

There are a number of top-level tuners and receivers which now incorporate the 25-µS de-emphasis and more are coming to the market right along. Dolby Labs has worked up a compensator circuit, which appears easy to build, inexpensive, and requires no power. The parts should be readily available. It naturally needs to be used with a Dolby B-type nose reduction unit.

E. P.

(Source: Audio magazine, Sept. 1974)

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