At the beginning of every new year, barely a few days after the tumult and the
noise and throbbing headaches of some few persons' intemperate celebrations,
we are faced with the prospect of attending the Winter Consumer Electronics Show
in Las Vegas. Apparently there is a groundswell of opinion in which a growing
number of companies find this winter trek to Las Vegas increasingly burdensome.
Pioneer did not attend, neither did many lesser fry, and quite a few of the "biggies" were
rather reluctant participants.
There was open doubt expressed as to the wisdom of two annual Consumer Electronics Shows. Many supported the idea of an annual show in June, alternating between Chicago and Las Vegas.
Whether this attitude would prevail in the best of times or is merely a reflection of the present bleak economic climate is a moot point.
In any case, the CES people claimed a new attendance record of better than 53,000 for the four-day run of the show.
Although this interest is encouraging, it would appear that buying was of the careful, cautious type that has characterized the last few conventions. Once again, video was clearly a dominant factor at the CES -- so much so, that some warnings were sounded about not for getting our audio roots and not getting burnt in the video boom. As always there were the querulous cries of "there's nothing new," and, as always, there were products which merited attention.
In my assessment the key word is selectivity, since it is obviously impossible to cover everything.
Although digital developments are more usually in the province of Audio Engineering Society Conventions, the WCES had some action in this area and one new product will have far-reaching significance. In a very low-key introduction (more of a "test the water" sort of thing) Technics demonstrated their Mod el SV-P100 digital audio cassette recorder. This unit looks very much like a Panasonic videocassette recorder, but it is specially designed for digital audio.
The system uses standard 1/2-inch VHS cassettes and conforms to the NTSC rotary head, slant helical recording format.
Instead of a large cumbersome PCM outboard processor, the SV-P100 has one of the biggest LSI (large scale integrated) chips ever manufactured. This is on a module, incorporated in the chassis of the SV-P100, and affords complete PCM digital recording and playback facilities. The digital recording system is the new EIAJ standard of 14 -bit linear encoding, with a sampling rate of 44.056 k per second.
The SV-P100 has a dynamic range of better than 90 dB, a frequency response of from 2 Hz to 20 kHz at +0 and -2 dB. Distortion is quoted at 0.01 percent, and it is important to note that this figure is given for 0 dB, not at the -20 dB level as is usually the case. I have been told that an electronic editor will be available when the SV-P100 is marketed. Most remarkably, the Technics digital recorder is not a blue sky project it will be avail able after the June CES in Chicago. The projected price is less than $3,000, and I have it on good authority that the price could be "significantly less" than the figure quoted.
This SV-P100 digital recorder could have a profound effect on the audio market. If performance specs are indeed as good as stated, it would make the sys tem superior to any professional analog recorder now on the market. While some high-end audiophiles would obviously be attracted to such a recorder, one must speculate about what they would record.
The performance of the SV-P100 would be vastly superior to any conventional off-the-air FM source, and phonograph records would not provide a really high-quality program source. Of course, live recording is possible, as it is with present analog tape machines, but opportunities to make high-quality recordings of this type are extremely limited. It would be logical to assume that prerecorded digital cassettes would be offered for these machines, especially since the production of this type of cassette is not technically difficult, and these cassettes would quite literally be duplicate master recordings.
Yamaha got into things digital by introducing a prototype of an AHD (Audio High Density) digital audio disc playback system. The AHD disc developed by JVC is of the grooveless capacitance type and has previously been described in these pages. The Yamaha AHD consists of the disc playback unit in one case, with all operational controls on the front panel, and a companion PCM processor in another case. Yamaha officials feel that the AHD digital disc system offers superior sound qualities, with significant advantages in economical replication since PVC is used for the disc and present conventional record presses can be used. The Yamaha people also stressed that while their AHD player is a prototype, it is "production ready." If the EIAJ approves AHD as the digital disc standard, Yamaha is all set to swing into action. Might as well mention that Yamaha was also showing their new B-6 magnetic field amplifier (made under license from Carver Corp.); its price is said to be about $900. This small black truncated pyramid weighs but 19 pounds and puts out 200 watts/channel. There are no controls on the unit; a warning light comes on if the amplifier's protection circuits are activated.
Meanwhile, the Carver people were demonstrating their C-1.5 amplifier. This is a further development of the magnetic field circuit, this time contained in a slim-line design 19 inches wide by about 2 3/4 inches high. Power output is said to be a whopping 750 watts per channel into 8 ohms, hence the "C-1.5" designation of the unit! Bob Carver states that the amplifier has a number of new proprietary protection circuits that enable it to be used with any loudspeaker regardless of its power-handling capacity. Availability is expected late this year with a price less than $800. Also available from Carver is a separate outboard hologram generator, a second generation of this device with improved performance in image stability, broader listening area, and the elimination of comb-filter effects. The C-9 sonic hologram generator is $279.
Carver stated that earlier embodiments of his sonic hologram circuit can be brought up to second-generation status for a nominal charge.
David Hafler continues to add to his line of amplifiers and preamps. At CES, he showed prototypes of his big new DH-500 amplifier -- a 250 watt/channel into 8-ohm MOS-FET design, said to have less than 0.015 percent distortion.
The massive heat sinks on the unit are cooled with a special low-noise fan, and the power supply has 40,000µF of capacitance. The DH -500 can be bridged to give a mono power output of 800 watts. As with all Hafler amplifiers, it will be available either as a kit or assembled.
These days, there is a lot of controversy about Class-A operation of amplifiers. There are engineers who steadfastly maintain that any of the newfangled circuits that employ dynamic biasing (or variations thereof) to achieve what is described as Class-A operation are just not the real thing. Jim Bongiorno of Sumo Electric is especially adamant on this point. He claims his new Model 9 amplifier is "pure" Class-A and in fact re mains so at all load impedances. His amplifier is rated at 70 watts/channel into 8 ohms, 120 watts/channel into 4 ohms.
Rise time is said to be 3 µS, and TIM is claimed to be nonexistent. Perhaps one of the most remarkable things about this amp is its price of $550, which is a new low for units of this class and output.
Sansui has been trumpeting the advantages of its new Super Feedforward amplifier circuitry at several of the recent AES Conventions. At the WCES, they showed the first fruits of all this new de sign work. Their Model AU-D11 is a 120 watt/channel into 8 ohms integrated amplifier. Very simplified, the feed-forward technique employs an error-correcting amplifier with a phasing network whose output is summed together with that of the regular amplifier stage. This permits nulling the residual distortion that remains (mostly TIM) after an optimal amount of negative feedback has been applied. The Sansui AU-D11 is said to have less than 0.004 percent THD, a slew rate of 400 V/µS, and a rise time of 1 .5 µS. A fast amplifier like this must have appeal for audiophiles, but may I gently suggest that most do not prefer integrated amplifiers. They dislike the idea of tone controls, filters, etc. and a phono stage that, in a sense, is thrust upon them since they are denied the choice of their own preamplifier.
At $1,000, this amp is obviously high-end, and Sansui would probably find more acceptance with audiophiles with a straightforward (no pun intended) power amplifier.
There were other interesting items of audio hardware at the WCES which I will report on next month. Most notable in audio software is the improving quality of prerecorded music cassettes. Mobile Fidelity is now in production of their first cassettes. Duplication is on a one-to-one real-time basis, using banks of JVC cassette recorders. The cassette tape is BASF Professional Chrome II, which means playback at the 70-4 setting of your deck. I sampled Steely Dan's Aja and found the reproduction to be out standing. Using a JVC KD-A7 deck for playback, high frequencies were well maintained, bass was clean and solid, overall distortion was very low, and, with Dolby B noise reduction, tape hiss was negligible. All in all, a first-class effort that puts cassettes up quite a few notches in fidelity.
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(Source: Audio magazine, Apr. 1981; Bert Whyte )
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