Video is the new glamour item of the consumer electronics industry, and this
was very positively demonstrated at the 1981 Summer Consumer Electronics Show
in Chicago, May 31 through June 3, at McCormick Place. Video products were
everywhere, in myriad manifestations, but in spite of the spotlight on video,
there were plenty of new audio products on view at McCormick Place and in satellite
hotels.
The only audio product which might be termed a "technological breakthrough" was the Sony/Philips Compact Digital Audio Disc. Sony, Philips and licensee Marantz were actually demonstrating prototype models which, needless to say, was a foretaste of the future and caused considerable excitement. The Compact Disc is 4.7 inches in diameter, is made of metallized plastic encapsulated with a plastic transparent protective scuff coating, and is thus impervious to dust, dirt, fingerprints, and scratches.
The disc rotates in a counter-clockwise direction, with the speed varying from 500 rpm on the inside of the disc (the disc is played inside out) to 200 rpm on the outside to maintain a constant linear velocity. The CD system uses pulse code modulation, with 16-bit linear en coding and a sampling rate of 44.33 kHz. A solid-state laser scans the information pits and flats at a rate of 4.3 mil lion bits per second. Theoretically, the disc can be recorded on both sides, but at present there is only 60 minutes stereo program on one side. An interesting point is that 30 minutes of four-channel playback is possible, and, with a stated channel separation of 90 dB, the signals would be very discrete indeed! The actual information density on a side of the CD is far greater than is needed for 60 minutes of music. Therefore, special purpose encoding can be employed to provide playback of individual selections in any sequence, to repeat selections, or even to display selection titles, playing time and lyrics of songs via a luminescent or LED device . or TV monitor screen. The usual digital specifications . . . 90-dB S/N and dynamic range, 20 Hz to 20 kHz frequency response, un measurable wow and flutter, etc. . . . apply to this Sony/Philips CD audio disc.
While the Digital Audio Disc committee of the EIAJ did not specifically name the Sony/Philips CD system as their unequivocal choice for a "standard." it certainly is the front-runner and has already been adopted by such companies as Bang and Olufsen, CBS/Sony, Crown, Dual, Matsushita, Nakamichi, Nippon Columbia, Onkyo, Polygram, Sony, Studer/Revox, and Kenwood. Polygram, the huge record conglomerate, is said to be setting up a plant to manufacture the Compact Discs, and CBS/ Sony is expecting to have ready a catalog of 100 CD recordings to coincide with the introduction of the CD system in Japan in the fall of 1982, with the U.S. introduction shortly thereafter. Projected price of the Sony/Philips CD player is expected to be between $400.00 and $600.00, with the discs between $9.00 and $12.00. From all this, one must conclude that by January 1983 the digital audio disc will be a reality, which, needless to say, will have a profound effect on many aspects of our industry. As I am sure you are aware. there have been numerous manufacturing problems with the laser-read videodiscs which have resulted in very high return rates.
Since the Sony/Philips system has virtually identical playback procedures, the quality control on the CD discs will have to be very stringent to keep the reject rate below one percent and ensure a viable system.
Another peek into the future of consumer electronics was provided at this SCES by the giant Matsushita Co. of Japan. Every few years. Matsushita holds a technology fair in Japan. This year they decided to schedule it in conjunction with the 1981 SCES in Chicago The massive Matsushita exhibit entitled "Matsushita Technology Today" occupied all 12,000 sq. ft of the huge Chicago Room at McCormick Place. This was in addition to the usual Panasonic. Technics, and Quasar exhibits on the main floor of McCormick Place. The special exhibit was divided into sections. each representing a particular manufacturing activity of the company. There were sections on health care electronics. featuring such advances as a bone-conduction hearing aid, and a Braille duplication system. Some absolutely fascinating new video technologies will be covered in my "VideoScenes" column. The business electronics section had such items as mobile facsimile systems and a Pana-copy automatic color-slide processor In the appliance electronics area, how about a microwave oven that "talks'. to you, acknowledging instructions! Component electronics featured microcomputer and memory devices, ICs and LSIs, sensors and opto-electronic devices. There were sections on sensory control, test instruments and production electronics, including an arc-welding robot. The audio item that attracted a great deal of attention was the SV-P100 digital-audio cassette recorder which was described in April and June 1981 issues of Audio. While it might be said that some of the exotic products in the Matsushita exhibit are some years away, there were none that should be de scribed as pure blue sky. The exhibit was certainly a revelatory experience and a tribute to Matsushita's dedication to high technology.
As you might expect, with laser digital-audio discs being demonstrated at the SCES, the doomsayers were out in full cry, proclaiming that the days of the LP record and all analog record-playing equipment were numbered. This is, of course, sheer nonsense. Even if the digital audio disc does not encounter any technical or production difficulties whatsoever, it will be years before any reasonably comprehensive catalog of soft ware exists, The analog LP record will be around for a long time, and there was plenty of new phonograph equipment offered at the SCES to underscore this point. Among audiophiles, the Linn-Sondek turntable has built up an enviable reputation for its "neutrality" and for not imparting any colorations to recordings during playback. Over the years, there have been a number of turntables, whose designer's goal was to knock the Linn from its expensive perch.
One particularly interesting design project with this goal is a joint effort be tween Sumiko, the importer of Grace and Supex cartridges, and SOTA Indus tries. both of Berkeley, California. Dave Fletcher, the canny head of Sumiko, is a physicist, and he teamed up with engineer Rodney Herman of SOTA, to de sign a turntable which they claim is based on Newtonian principles. Although there is one basic design on the turntable, there are two different models.
The Gem will be sold through Sumiko and it differs from SOTA's Sapphire in being equipped with either the Grace 707 Mk II tonearm or the Grace 747 Tonearm. The SOTA turntable is sold without a tonearm. Both turntables em ploy an 18-pound subassembly made of a special zinc alloy, with added lead and synthetic damping. A special four-point suspension is used with a resonance frequency of 2.55 Hz. This is combined with a 12.5-pound cast-zinc alloy base with compound damping. Some 40 per cent of the weight is concentrated near the rim of the platter to provide a flywheel effect. Under the platter spindle is an inverted sapphire disc bearing, said to be accurate to one wavelength of light. The bearing is at the table's center of gravity. The sapphire disc rides on a hardened chrome-steel ball, claimed to be accurate to 1/10,000,000 of an inch. Most turntables have shafts which extend from the platter. In the SOTA design the thrust shaft remains fixed and immobile. Rotation occurs only at the center of gravity and any unbalanced forces are effectively nulled. In the Gem model, the built-in arms are factory balanced and mass-loaded to compensate for the weight of the sub-assembly and platter. In the Sapphire model, there are variable mass-loading options to adjust for the specific weight of the tonearm selected. In both models, with this approach, total mass of the entire turntable system remains constant, and this offers a combination of static balance and dynamic stability. In the SOTA model, a special belt drives the outer rim of the platter from a brushless d.c. servo motor with 33 1/3-rpm and 45-rpm speeds electronically switchable. In the Gem model, the belt drive is the same but employs a different motor with push-button selection of the two playback speeds. Rumble for these turntables is claimed to be-60 db unweighted at a reference of 10 cm/ S at 1000 Hz. The price of the Gem is $725 with the Grace 707 Mk II arm and $800.00 with the Grace 747 arm. The SOTA version of the table is $650.00.
A new Denon turntable offers an entirely different "brute force" approach to its design. The platter weighs 35 pounds, there is a 150-pound turntable chassis and base, mounted on massive springs, and the drive is direct via a huge cogless quartz-lock motor. A special arm is provided with the system. Price of this backbreaker is $5000.00.
Lux created quite a stir with its vacuum hold-down turntable at the 1980 SCES. Now they have introduced the Model PD-375 turntable, which, in contrast to the previous model, is a direct-drive unit with a built-in arm. The all-important vacuum hold-down feature is there, but this time the vacuum is established with a manual pump instead of the automatic electric system on the earlier turntable. The good news is that you can now enjoy the disc-flattening and vinyl resonance damping of the vacuum hold--down for $599.95 instead of the whop ping $2995.00 of the original model.
For many years the highly regarded British-made SME tonearms were distributed in this country by Shure Bros. I ran across Alastair Robertson-Aikman, the ever-debonair director of SME at the Show, and he informed me that after a very successful collaboration with Ortofon on a cartridge/arm interface, he had appointed Ortofon U.S.A. as sole distributor of SME products in this country.
Those who are interested in 16-inch tonearms will be glad to know that SME has introduced an updated version of its classic arm design in that length.
Speaking of tonearms, no SCES would be complete without the introduction of some really exotic design. This year's winner is probably the Souther Equamass linear-tracking tonearm. The designer, Lou Souther, has produced a unique arm which is molded from epoxy resin and incorporates millions of tiny 0.0002-inch diameter hollow-glass spheres (with a specific gravity of 0.8) and a special aluminum tube 3/32-inch diameter. The total weight of the arm is 1.25 grams! Obviously, this is less than the tracking force of many cartridges.
Then, on the back of the arm, Souther positions a counterweight, equal to the weight of the cartridge, at a distance from the horizontal pivot bearings slightly less than the arm's effective length. This enables him to set the exact tracking force for a particular cartridge. The arm is driven laterally across the record by the record groove itself, and ultra-low friction bearings are used. When this arm encounters a record warp and the stylus assembly starts its upward motion, it is met with a total mass just over twice that of the cartridge: for example, this could be 4 grams cartridge, 4 grams counterweight, and arm mass 1.25 grams for a total mass of 9.25 grams.
Souther claims there is never enough up force generated to compress the cantilever assembly, and on the down side of the warp, the arm mass is so low that little or no inertia effect is produced. The stylus tracks the grooves perfectly, with no significant changes in tracking force, Souther claims. If you strike the turntable laterally from the side, the shock can cause the counterweight to oscillate left and right as much as a quarter of an inch, yet the stylus will not leave the groove! This super tracking ability is said to provide a much cleaner, more open and highly detailed sound than can be heard from conventional arms. This intriguing arm will be priced at $500.00.
Dennesen was showing an unusual head amplifier for moving-coil cartridges called the Cetus, which is said to operate as a true differential–input transconductance amplifier, treating the moving-coil cartridge as a current source rather than a voltage source. It is said to be derived from a sensing amplifier in a computer's analog-memory system. The Cetus uses a matched pair of high-cur rent thermally coupled transistors in its circuit. The unit is a.c. powered from a remote supply. There is a variable 2- to 120-ohms impedance-matching control, which also varies gain from 26 to 35 dB depending on the impedance. Frequency response is said to be 7 Hz to 250 kHz ±-0.01 dB. Input overload is rated at one volt and output is 10 volts. S/N ratio is listed as 85 dB and rise time is a very fast 500 nanoseconds at 2 volts output.
No price available.
Moving over to records to really give all this fancy phono gear a tough work out and a super sound source, Mobile Fidelity has introduced their UHQR (Ultra High Quality Record) series, which was developed in conjunction with JVC. It is a "spin-off" from JVC's work in video disc technology. The UHQR records weigh in at approximately 200 grams, which is a helluva thick record. Points of superiority include channel separation 10 dB better than standard Mobile Fidelity records which use JVC CD-4 super vinyl. Intermodulation distortion is reduced to the theoretical limits of vinyl.
Vinyl resonance has been removed from the audible range. S/N ratio is 10 dB better than standard Mobile Fidelity re cords. Groove depth on the UHQR can be 3 mils or more. Pressing cycle on UHQR is 2 1/2 to 3 minutes compared to 50 seconds for standard Mobile Fidelity pressings. Only one press in the world is set up for UHQR product and Mobile Fidelity has exclusive rights to its use. The first three releases in the UHQR series will be Pink Floyd's Dark Side of the Moon, Supertramp's Crime of the Century and Earl Klugh's Finger Paintings.
Only 5,000 pressings will be issued of each limited-edition title. If you really dig this music and you want these super pressings, they will set you back a rather breathtaking $40.00 each! Mobile Fidelity has stated they will not be sending out any review copies of these records. I can't tell you what these particular numbers will sound like, but I already have two UHQR discs with other program material, one a Mozart piano sonata simply stunning in its realism. There just isn't any surface noise, the frequency response goes way out, distortion is the lowest I have ever heard from a record, and volume level and dynamic range are overwhelming. An outstanding achievement, and if the oncoming digital discs mean the end of the analog LP, to paraphrase old Winnie . . . "this is their finest hour." Many more audio products from the 1981 SCES next month.
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(Adapted from: Audio magazine, Sept. 1981; Bert Whyte )
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