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I see that through the time-traveling magic of publishing deadlines, I am writing for the January issue of Audio in the bright new year of 1977.
Being a first-class, card-carrying pundit, it is my sworn obligation to make some prognostications as to whither goest audio in 1977. First though, I have a few gripes that need airing.... At the top of everyone's list is the abominable quality of record pressing in this country. A very high percentage of the records are simply incredibly bad, and the problem has reached epidemic proportions. Getting a record which doesn't have dish and/or pinch warpage is almost an occasion to pop a bottle of champagne.
As for record surfaces...the Rice Krispies people ought to sue for infringement on their Snap! Crackle! and Pop! theme. Add to these time-honored anomalies such things as cyclic swishes and thumps with assorted low frequency rumblings, and you would swear the records were pressed on low-grade concrete. The worst part of all this is that you can dig into your record library and find any number of records made 15 to 20 years ago which are not afflicted with the aforementioned defects. What has gone wrong with today's pressings? How has record quality reached it present low state? Putting aside such emotional responses as "they don't give a damn" or accusing the record companies of sheer venality, there appear to be several reasons for these pressing defects. No matter how the record companies prattle on about how the "new lightweight records" have "better moulding qualities," the fact is that the discs are as much as 50 grams lighter than the records of a few years ago and consequently thinner and more flexible...and thus more susceptible to warpage. Because of the sales advantage of "factory-sealed virgin recordings," virtually all records today are shrink-wrapped. This process is easily capable of warping the cardboard record shucks...and the thin record inside the shuck as well.
While there undoubtedly is much dish and pinch warpage in pressings due to mishandling in the cooling cycle, in the opinion of a number of record company engineers I've talked with, it is the shrink-wrapping which is most highly contributory to record warpage. Needless to say, the simple expedient of eliminating the shrink-wrapping runs right into the "factory sealed" problem. What we need, then, is some new kind of seal that will guarantee the record is virgin, but will not cause warpage.
The reduction and preferably elimination of surface noise is a more formidable problem than disc warpage.
During the oil embargo and the subsequent shortage of polyvinyl chloride (PVC), much substandard PVC powder was used for pressings...the very worst of which was that concocted from recycled, ground-up old or surplus records. Now there is no shortage of PVC, but it appears that there are variations in the in the product from several manufacturers. Most record companies have their own formulations of pressing compounds, which contain many items besides the PVC (for example, lubricants such as lead stearate, stabilizers, plasticizers, etc.). The percentage of PVC in the compound varies, but it may surprise you to know that although records may be advertised as "100 percent pure virgin vinyl," this is rarely the case. The different pressing compounds have varying properties of melt temperature, flow viscosity, and other parameters necessary for good moulding. The idea, of course, is to eliminate such things as bubbles, voids, groove pulls, or lack of proper fill. The noise output of the record is therefore an index to the success of the moulding process.
Time = Sonic Quality
However, there is another aspect of record pressing that can have an effect on the noise of the pressing and its physical deformation. This simply is in the timing of the record pressing cycle. There is one timing called the "pop" cycle and another called the "symphonic" cycle. The symphonic cycle is of longer duration than the pop cycle and could be considered a more "careful" pressing operation.
The record stampers are in more extended contact with the pressing compound, and the molded record stays longer in the press for more controlled cooling. Generally speaking, if someone wants a higher quality pressing with minimum noise, he specifies the use of the symphonic cycle. The rub here is that such cycling is more expensive since it takes more time.
Unfortunately, the generation of noise in a recording can go all the way back to the cutting of the lacquer master. The material the cutting stylus dislodges from the groove while cutting the lacquer is called the "chip." It is usually removed by a vacuum suction device positioned very close to the stylus. Believe it or not, the way the suction tube is adjusted can effect the angle of chip removal, and if this angle approaches 90 degrees, this can generate a certain kind of noise. Far more noise can result, however, from the electroplating and processing of the lacquer master. I've gone into this before...and it can be summed up that time-accelerated plating, permitting too rapid a deposition of metal, and the less than careful grinding of the backs of the stampers can both cause a broad frequency spectrum of noise. It takes time, which means money, to do a careful lacquer processing job, and in the hurly-burly pressure of the mass record market, this rarely is the case.
Okay...so a lot of lousy records are produced...what can be done to improve this situation? It has been argued that the record buyers in the mass market have neither the quality of playback equipment nor the aural discrimination to be bothered by defective records. Be that as it may, component hi-fi equipment continues to be sold to a great many people, and this has been going on for quite some years. By now, there is enough good equipment in use to constitute at least a "mini" mass market. Unquestionably, thousands of these people have complained to their record dealers and to the record companies about defective records...to no avail. Unless the record companies start to receive complaints by the hundreds of thousands, nothing is likely to change.
Even though such mass protests would be for their ultimate benefit, by the perverse nature of things, it is unlikely that many people would embark on such a crusade.
If the record companies claim that special time-consuming processing is necessary to produce high quality pressings, which means extra costs, the only way to get such recordings is in the establishment of special "Audiophile" or "Super-Fi" editions of recordings. These would cost a dollar or so more than the standard pressings, but their quality would be guaranteed by the companies issuing such recordings. Before you vent your spleen on me for such an outrageous suggestion, please remember we had a precedent for just this sort of thing in the Westminster Lab Series of the late 1950s, which were specially mastered, processed, and packaged.
There are many superb recordings being made today, and if it takes a special high quality pressing to do them justice, albeit at a premium price, it would seem to me that this is a worthwhile idea. Well, I got that off my chest...so on to the prognostications.
In general, audio in 1977 will be a year of proliferation of high-end equipment, with ever increasing technological sophistication and of equipment with new "convenience" features. There will be a great increase in the use of digital technology, much of which will be applied to some rather exotic remote control devices. In fact, remote control of many additional audio functions will be the big "in" thing in '77.
You will see more open-reel and cassette recorders using digital logic in their transport systems. Also becoming a more common feature on these tape machines will be the easy adjustment of azimuth together with front panel adjustments for bias and equalization. In spite of a general "wait and see," lukewarm attitude toward the new Elcaset format, I predict that by this time next year, the Elcaset will be firmly established. A large part of the reason for this will be the availability of prerecorded Elcasets, which will be not only a viable alternate to the disc, but superior to it in many respects. The Elcaset is also likely to play an important role in the "second coming" of quadraphonic sound.
There is much "behind the scenes" activity in four-channel sound, with several significant advances in recording technology, and you will see very advanced demodulators and decoders, new high-powered four channel receivers, and some definite action in the quadraphonic FM broadcast situation.
There will be increasing use of time delay in audio systems, with several new devices appearing on the market.
This also aids and abets the revival of four-channel sound, since time delay requires the addition of another stereo amplifier and a pair of speakers.
Once Joe Audiophile has this set-up, it most certainly will occur to him that for a very modest outlay he can acquire a demodulator or a decoder and have quadraphonic facilities as well.
The power race in receivers will continue with some models topping 200 watts per channel. Their makers might offer a small fork-lift as an option to handle these behemoths.
Oddly enough, in the separate power amplifier category, while there won't be any dearth of super power output units, the emphasis will be more on refinement and sophistication, rather than power. You can look for more class A amplifiers and amplifiers in which much careful design work has been done towards the reduction or elimination of TIM with emphasis on fast rise times and slew rates. In pre amps, there will be models with all the multi-function "whistle and bells" facilities, but here too you'll see a trend towards simple and more technically sophisticated units. Moving-coil phono inputs will be built-into many pre amps, and you look for wider use of stepped, detent-type tone and volume controls.
More turntables will boast quartz oscillator, phase-lock-loop circuitry and will have more massive bases.
Tone arms will emphasize low mass and lower friction. One arm we know of will use 24 ruby bearings and have a compensating device to control resonance interaction between differing cartridges and the arm.
Loudspeakers will show a definite trend to larger size, as in days of yore.
However, enclosures will be the result of much advanced measurement and computer technology. You can also look for more speakers that are bi- and tri-amplified with their designs predicated on this concept.
In the "dark horse" department, the money is on several new noise reduction devices. And finally, 1977 will see quite an emphasis on direct-disc recording-with at least one major symphony orchestra making this type of recording! 1977 looks to be a banner year for audio! Happy New Year!
(Source: Audio magazine, Jan. 1977; Bert Whyte)
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