Dear Editor (Dec. 1972)

Dolby Broadcasting

Dear Sir:

While going over some back issues of your excellent publication, I read a very interesting letter in the January 1972 edition on the pros and cons of Dolby "B" processing of FM stereo broadcasts. As we have had some small experience in this medium, we'd like to add some comments to the writer's conclusion that it wasn't worth the trouble.

It is extremely frustrating to live 50 or 60 miles from the only FM station in the area, or from the only station with programming one enjoys. Just as the cassette tape medium is dramatically improved by Dolby "B" encoding/ decoding, so will fringe-area reception be improved, although crosstalk from other channels, flutter fading, and multipath problems won't be helped a bit. One engineer suggested that what FM stereo really needs now is the abolition of the steep pre-emphasis curve, and the mandatory imposition of Dolby. At least one manufacturer has announced a simple, cheap Dolby circuit in chip form, which could add not more than $10.00 to the cost of a new tuner. But, alas, since the FCC would be more concerned (and perhaps rightly so) with the compatibility of such resulting broadcasts with the countless numbers of tuners in existence, it shall never be... . What appears to me to be a major stumbling block to hinder the use of the Dolby process is the wide-spread use of high-frequency clippers/limiters, such as the CBS Labs "Volumax" and the Fairchild "Conax," which roll off the treble response in proportion to the input level, in order to reduce the danger of overmodulation. Most FM listeners are totally ignorant of such devices, and my experience shows that fewer still can perceive their operation until they have the technique explained and demonstrated.

For a small core of audio purists (myself included), the resulting sound is highly unpleasant and unmusical, and we sit back in our chairs grumbling about the listening fatigue from high-frequency square waves and wish that the stations would simply cut their overall dynamic range back a few dB instead. Imagine the sound of a Dolbyized broadcast on a station which also employs a "Volumax," as heard on a non-Dolbyized receiver: the low passages are crisply over-brilliant, and the fortes are by contrast horribly dull and wooden. No amount of tone-control manipulation could possibly restore original sonic balance.

I am also pessimistic regarding Dolby FM from a personal experience. After promoting a special two-hour long program in not only Dolby "B" encoded sound, but also utilizing E-V 4 encoded tapes and discs, and running the show in great anticipation of listener approval, we received not ONE comment from any listener, though our engineer loved it. We customarily hear from many enthusiastic supporters of our popular and classical music programs, but to our total surprise, this special effort drew a complete blank. Nobody cared to let us know, though we literally begged for phone and letter response, how the program appealed to his audio sensibilities with or without Dolby in the playback.

A further quadraphonic show the following week, says Dolby, drew so many calls we couldn't answer the phone and run the board at the same time. Maybe it was an especially good television night... . Now that I think of it, perhaps Dolby in TV audio?

-Stephen R. Waldee, Classical Program Director, Peninsula Broadcasting/KPEN San Francisco, Calif.

We understand that, among others, WQXR in New York and WFMT in Chicago, have been extremely satisfied with the results of their tests. We would be interested in hearing from other station personnel about their experiences. -Ed.

Dolby Cassette Deck

Dear Sir: In the cassette and cartridge recorder section of your September 1972 Directory issue (pages 94 to 98) you correctly indicate in the column which lists Special Features that the following cassette machines incorporate Dolby noise reduction: Advent 201, Advent 202, Concord Mk-7, Harman-Kardon CAD-5, and Hitachi TRQ-2000. By use of the code letter "D" to identify other machines with Dolby, you were using a symbol which many readers might have missed, for by failing to make any indication, readers might not realize that all of the following machines listed in your Directory also have the Dolby circuits built into them: AKAI GXC-65D, Concord Mk-IX, Fisher RC-80B, Harman-Kardon HK-1000, Kenwood KX-700, Lafayette RK-D40 Panasonic RS263US, RS277US, and RS276US, Pioneer CT414ID, Radio Shack SCT-6, Sansui SC-700, Sanyo RD-4300, Sony TC-134SD and TC-160SD, Tandberg TCD-300, TEAC A-350 and A-250, and Wollensak 4760A. In addition to those in your table, seven more machines with the Dolby circuits are available in the United States. These are: AKAI GXC-46D, Beltek M-1150, Bigston BSD-200AS, Panasonic RS271US and RS279US, Sharpe RTX-3000, and Wollensak 4780. Because your Directory issue is so widely used in the industry for reference purposes throughout the year, I hope that you will bring this information to the attention of your readers through your letters column.

Dolby Laboratories, Robert Berkovitz, Dolby Laboratories, London, Nagra Magnetics is located at 19 W. 44th St., New York, N.Y. 10036.

Audio Research

Audio Research points out that the price of their Magneplanar speaker systems is $995.00 a pair and not $995.00 each as might be thought from the September Directory.

(Source: Audio magazine.)

Also see:

Editor's Review (Feb. 1973)

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