Box 392: Letters to the Editor (Vol. 2, No. 3, Spring - Fall 1980)

Since we intend to continue this column in our forthcoming biweekly bulletins (see announcement on page 2), and since that tight new format leaves no room for the various forms of long-windedness and/or irrelevance we occasionally allowed to slip through here in the past, we must emphasize once again that only letters from which our readers can learn something-anything!-will be deemed suitable for publication. Undocumented disagreements with our findings by individuals without a track record in audio testing ('Silver cable does so sound better, turkeys-are you deaf or something?'') are, for example, of no editorial value whatsoever. Nor is 'What's a nanosecond-you guys use funny words my local hi-fi salesman can't explain."" Manufacturers whose equipment we review will continue to have the privilege of having their letters printed in their entirety. Other correspondence may or may not be excerpted, at the discretion of the Editor. Ellipsis (. . .) indicates omission. But please, everybody, keep it as short as you can from now on. Letters should be addressed to The Editor, The Audio Critic, Box 392, Bronxville, NY 10708.

The Audio Critic:

In the past, Win Laboratories has al ways maintained an ''open door policy'' at our research and development facilities as well as at our factory to friends, peers and audio journalists alike. This was done in good faith that the more information in re search and development we can share, the better it would be for the continuing growth of our American audio industry.

However, within the last year and a half, this privilege has been jeopardized by one audio journalist, who used the research information he had received from Win Lab oratories to help a foreign firm develop a product similar to ours in appearance and fundamental design, without prior authorization by or consultation with Win Laboratories. Although the consequences of such actions will mainly affect manufacturers in the forefront of the industry for the short term, it is the general public that pays the final price in the long run.

Manufacturers in our capacity rely on the integrity of audio reviewers to print an honest opinion. However, when a reviewer claims that a new product 'is, in terms of parts, design and construction quality (not to mention aesthetic beauty), in the same class as'' our SDC-10, we expect to see a truly remarkable product. When such expectations are unfulfilled, the credibility of the particular journalist becomes tainted. It is unfortunate from our perspective that many people will not have the opportunity to see both products side by side and judge for themselves.

For this reason, although we will still retain an ''open door policy,'' specific de sign information will only be revealed after a written nondisclosure agreement has been signed.

We deem this action regrettable but necessary.

Yours very truly,

Dr. Sao Zaw Win President Win Laboratories, Inc.

Goleta, CA

We're glad Dr. Win didn't deign to mention the name of the audio reviewer in question, since printing it would have conflicted with our previously established policy of disregarding our journalistic bad mouthers, of whom this same individual has been the most obsessive (he seems to be thinking about The Audio Critic night and day) and the most shrilly personal, though probably the least important. Some of our readers will know who he is from the circumstances of the case; the rest of you may consider yourselves lucky.

We can tell you, however, the name of the ''foreign'' turntable Dr. Win is referring to: it's the Oracle, made in Canada. We have a sample of it in our possession and are planning to review it in one of the early issues of our forthcoming biweekly Bulletins. We're willing to go on record right now, though, that it isn't a Win SDC-10 by any stretch of the most dilettantish imagination.

There are basically two lessons to be learned here. One is that an ethical reviewer owes his readers full disclosure regarding any personal interest or involvement he may have in a product he is reviewing. The other is that audio designers must beware of worshipful techno-groupies who want to know all about the nuts-and-bolts engineering details. The one who is picking your brain while he is kissing your behind may be an industrial spy.

-Ed.

The Audio Critic:

We were mostly overjoyed to read your comments about speaker wires and audio cables in Volume 2, Number 2. The wide spread confusion and misinformation about speaker wire has especially been aggravated by the cultists, mysteriosos and wishful thinkers pushing their own theories of how electronics travel from amp to speaker (and back). Thanks for the debunking.

Your point about thinking numbers, not labels, is well taken if one considers resistance alone, but each wire presents a combination of cumulative changes to an audio signal. These changes include the inductance and capacitance you mentioned, plus a couple of phenomena for which no name yet exists-as well as resistance. In taking that part of your article literally, an enthusiast would be confused whether or not to switch from zip cord to something better in a run of 8 to 15 feet.

In blind listening tests, our panel was able to distinguish with better than 90% accuracy between speakers connected with 5 feet of Monster Cable compared with 5 feet of 18 gauge. We know of a case where the sound of a two-module speaker improved noticeably on the top end when an 18-inch "jumper" between top and bottom was replaced with Monster Cable. There are several cases where consumers and manufacturers have used Monster Cable to internally wire their speakers and have reported a discernable improvement. This leads us to conclude that 18 gauge should not be used under any circumstances, and that even in very short runs Monster Cable would be sonically preferable to zip cord.

We agree completely with your comments about series inductance and shunt capacitance affecting the stability of amplifiers. Most audiophiles are not capable of determining whether a particular *exotic"' speaker wire is going to have a detrimental effect on a given amplifier, but we can make this (gross) generalization:

Many amplifiers which are of wide bandwidth design, employ high slew rates and utilize a speaker feedback loop, may tend to destabilize when connected with a speaker cable that has ultra-low inductance and (by definition) high capacitance characteristics.

It should be pointed out that we haven't found an amplifier yet which is adversely affected by Monster Cable.

One point where we disagree is the nature of the status quo. "Would any audiophile use thinner wire for such a long run?"' Our surveys indicate the majority of audiophiles, having made an otherwise intelligent decision on their other system components, are still using whatever speaker wire the dealer was giving away at the time.

Even figured on purely resistive effects, at 4 ohms 20 feet of 16 AWG wire would give the following result in a 100-watt/channel amplifier with rated damping factor of 100:

Available power to speaker--92 watts Effective damping factor--19.9 If the 8 watts (0.3 dB) aren't important, the uncontrolled bass output below resonance point of the woofer is. These problems are exacerbated by the use of common speaker fuses as you point out on page 27.

So here we have a not-too-theoretical case where the performance of a system similar to your reference system '"B'' ($2700 +) could be noticeably compromised by a few feet of giveaway wire. While the same length of Monster Cable won't give you back all the lost wattage and damping, it will certainly minimize those losses.

Lastly, we get back to the most important criterion-listening. Without naming the phenomena involved, may I suggest that you duplicate one of our experiments:

Compare 30 feet or more of Monster Cable to an equal length of either commercially available 10 or 12 gauge stranded wire or Romex. We used wide-band noise and full-range music for the comparison.

Since there are similar amounts of copper conductor involved, the audible differences should be attributable to construction and stranding.

Agreed, sometimes we're talking about some relatively subtle differences, but in a climate where a consumer must spend approximately $500 to change from an FR-1 Mk 3 to a Koetsu, the results of switching to Monster Cable far outweigh the extra cost involved.

Thanks for listening!

Best regards, Joe Abrams National Sales Manager Monster Cable San Francisco, CA

We won't deny, and never did, that in a given chain of components an audible difference may result when the speaker wire is changed. What we do deny is that such an audible difference will be unfathomable in terms of resistance, inductance, capacitance, dielectric properties, diode effects at joints, RF pickup or other known electrical phenomena. We insist that the burden of proof is on those who can hear still other differences due to "phenomena for which no name vet exists''--not on us squares who can't.

We have yet to hear a successful demonstration of the no-name stuff.

What the exact thresholds of audibility are when it comes to small differences in R, L, C, etc., is an open question; your observations are as valid as ours or anyone else's.

We cant ell you, however, that your damping factor analysis is invalid. As Richard H. Small himself points out in one of his classic papers, damping factor specifications are much more meaningful at 50 Hz than in the midband, and nominally 4-ohm speaker loads aren't 4 ohms at 50 Hz but well into the double digits. Therefore the effect due to the 16-gauge wire will be much smaller than you claim. ''Uncontrolled bass out put' is a vast exaggeration.

In any event, you like Monster Cable and we like Monster Cable, so why should we fight?

-Ed.

The Audio Critic:

I was about to send you. . .a request to return my tonearms when surprise, surprise, along comes The Audio Critic with its review, as you stated, two years in the making. The review is full of assumptions which compel me to correct and clarify.

The Rabco mod you reviewed is not the first one but an improved version sent to you at request over one year ago. This arm used a hollow balsa shell. One of two other reviewers had described the sound of this arm as ''magnificent'" and the other in a letter to me as ''superb''. Neither of them has had an arm as cosmetically attractive as the one you have. The slight coloration you refer to has for the last six months been removed by the simple expediency of packing the shell with foam rubber. I have a letter written by an audiophile whose opinion differs from yours concerning the merits of your 'best tone arm''. He prefers the Wheaton Rabco to his FR-64. His Rabco tone arm was deadened by the above-mentioned method.

Your review was interesting because it indicated there was no sonic difference be tween the Rabco with a hollow shell and the Wheaton 240 with a hollow shell. In other words, the importance of straight-line tracking is somewhat exaggerated. A pivoted arm, correctly designed, can sound as good or maybe with correct geometry even better.

The only Wheaton 240 that [ have cared to sell to date had its hollow shell deadened by foam rubber. With all the errors you might have found in the 240 but didn't, I think it's remarkable that your only com plaint could be the hollow shell. With the recent acquisition of certain equipment, the shells of both arms will be milled from solid hard balsa. Both the solid and rubber filled shells in my opinion are deader than any metal arm, and that is the reason I opted for balsa, not because 'lighter is better." For tracking warped records, lighter is better. In addition, the balsa arm affords more isolation to any cartridge, which is the reason for the ''magnificent, superb' sound.

The Wheaton 240 is now a 250, this to accommodate the Kenwood KD 600, for example, which is slightly different from the KD 500. The cueing arm is shorter to accommodate the Oracle turntable. The axis of the vertical pivots is canted 22 degrees.

The head shell will be made of solid balsa, and the geometry further improved.

Beauty is in the eye of the beholder, and since everything was done for a purpose, its appearance is usual in many respects.

Yours truly, Herbert Papier Wheaton Music Wheaton, MD

We could only evaluate the damping characteristics of the samples sent to us, not of variant versions owned by others. As for pivoted vs. straight-line tracking arms, we agree that various construction details may end up having a greater influence on the sound than lateral geometry; however, we can readily hear the maxima and minima of a correctly offset and overhung pivoted arm as it traverses the record, so we still believe in the inherent superiority of the SLT concept. Lastly, solid balsa wood is not the acoustically deadest material you could use, although it's a lot deader than some.

-Ed.

The Audio Critic:

Thank you for printing my letters, but unfortunately I find your replies unacceptable, and for the benefit of your readers a further response is required.

You seem to be unaware that the original and earliest solution to the problem of tonearm geometry was devised and presented by Percy Wilson, Britain's first and most distinguished hi-fi reviewer, in the Gramophone during 1924, when he was the first to use offset and overhang principles.

Second, an arm should be designed not for minimum tracking error but for mini mum distortion-a different thing, since distortion becomes greater (for a given error angle) as the groove radius become less. It follows a simple law, not a square law. The geometric technique Percy Wilson described became common in Britain and was taken up much later in the U.S.A, in fact ''re discovered'' (P.W.'s own word) by Bauer and Baerwald, who both got their calculations wrong. The Master had to put them right in another article which also appeared in Gramophone. Baerwald's 1941 equations were approximations, but a further analysis by J.K. Stevenson in 1966 was not. In fact, the basis of Stevenson's arm design technique ensures that peak distortion levels re main constant as an arm tracks inwards;

most importantly he provides an arm design technique that allows the best values of off set and overhang to be found for any particular length of arm, including one optimized purely for 12°' LP discs.

I have shown The Audio Critic's alignment table to J.K. Stevenson, who says as follows: '"The quoted values of overhang and offset angle are obtained by disregarding all other forms of distortion and making the tracking error maximum at the inner grooves of a 12'' record. The maximum distortion is then slightly less than in my design, but it occurs on the worst possible occasion, namely at the inner grooves where all other forms of distortion are maximum.' Finally would my American friends please note that the incorrect term antiskating is a complete misnomer; the correct expression is sidethrust or bias, and the adjustment is called sidethrust correction or bias compensation.

Yours sincerely, Gerald Bearman

Director Mayware Ltd. (Formula 4)

England

After your third communication to us on this subject, we must reluctantly conclude that you have no clear understanding of the basic mathematics involved and apparently rely on others to supply you with arguments, which then become garbled in your translation.

Baerwald's 1941 solution is not an approximation, nor did he get his calculations wrong, nor could someone as intelligent as Percy Wilson have said anything so asinine.

You yourself quote J.K. Stevenson as confirming that our Baerwald-derived alignment table minimizes the maximum values of distortion, which is what a purely geometrical solution is all about. What Stevenson is trying to tell you, and what you don't appear to grasp, is that his design also takes into consideration an additional factor totally different from geometrical tracking error--namely inner-groove distortion due to loss of stylus contact with the groove wall. This is at least a rational argument at first blush (we shall take it up in greater detail in our forthcoming Handbook), but it certainly isn't a refutation of Baerwald. In any event, a modern stylus like the Vital or Paroc or especially the Van den Hul hardly knows the difference between outer and inner grooves-it traces the innermost better than a 1966 spherical stylus did the outermost. What's more, tracking distortion and tracing distortion are in quadrature (90° phase angle between the two) and therefore not cumulative in a simple way.

Speaking of the benefit of our readers, they should also be informed that your arguments are, on top of everything else, obviously self-serving. Your advertisement in the back pages of Audio offers a $10 protractor with a dire warning against ''out dated 1941 tonearm geometry (that) gives maximum distortion from the critical listening area instead of (the) required minimum.'' This language is so blatantly misleading that after we saw the ad your high-pitched defensiveness suddenly began to make sense.

As for antiskating/sidethrust correction, it's exactly like truck/lorry, apartment/flat, candyl/sweets or snake oil/Mayware. American/British equivalents.

-Ed.

The Audio Critic:

I would like you to comment on what I see as a commonly held ''Audio Myth': on the record jacket of most Mobile Fidelity master recordings there is an essay on the MFSL philosophy and technique of record mastering. Included is a statement on 'record memory'' that I find hard to swallow. MFSL contends that softer vinyl pressings experience ''stretching'' of the groove walls from stylus pressure, which can last up to 24 hours before returning to its ordinary shape. This effect is supposed to be audible on most ordinary recordings.

I differ with this assertion for two reasons. First, I presently own a system of Reference B quality with the cartridge (an FR-1 Mk 3F) properly aligned, and I have never heard any audible degradation of the sound quality of a record played 2 or more times within a short period of time. Second, considering the comments made by Mr. Cotter in the first installment of your *'state of-the-art seminar'' in Vol. 2, No. 1 pertaining to the interface between the stylus tip and the groove wall, it was stated that the stylus does not play the surface but the subsurface of a groove wall. With the stylus 'sinking' into the groove wall only 3 or 4 microns (actually he said only 0.3 or 0.4 microns- Ed.), it does not seem to me that even if the vinyl did not immediately ''bounce'' back to its original shape that there would be an audible difference in sound. I see no reason why the vinyl should not return to its original shape after the stylus passes over it, however. Considering the small scale involved, as Mr. Cotter so aptly states, one cannot discuss the elastic properties of vinyl solely in terms of classical physics--the quantum mechanical effects must also be reckoned with.

All in all, it appears that many audiophiles have fallen prey to a popular misconception. I have had audio enthusiasts and dealers alike swear up and down that "'record memory' does indeed exist. I would appreciate your comments on this subject. If I am correct, then tally one more strike against the ''audio sophists''; if not then please correct my errant ways.

Sincerely, Lt. Dale W. Wittig United Sates Army What Mobile Fidelity Sound Lab actually claims is that their so-called Super Vinyl, available only in Japan from JVC, has no "memory," whereas ordinary vinyl does.

Vinyl comes in different grades and qualities, some much softer than others. One can't really make any sweeping generalizations about the integrity of the groove walls after repeated plays. In rare cases the vinyl is never the same again after a single play. If vinyl memory were a major problem, how ever, it would be impossible for us to run cartridge, arm or preamp A/B tests, all of which require playing the same passage on a record over and over again. The very fact that we haven't observed any significant inconsistencies in the course of these tests seems to indicate that vinyl memory, if it exists at all, is no big deal. We refuse to state categorically, however, that it cannot exist under any and all circumstances.

-Ed.

The Audio Critic:

Over several years of following the audio press (both mass market and high-end publications such as your own), I have consistently noted a peculiar phenomenon.

Often, I will find that a speaker system which has been highly acclaimed by under ground reviewers and other such ''high end' sources will be panned by the less specialized publications. These reviews will suggest, either overtly or covertly, that while the speaker is excellent in areas which golden-eared audiophiles deem important, it nevertheless lacks the punch and dynamism necessary to satisfy lovers of rock and other such popular music. There is often the subtle insinuation that the system is some how "too neutral' to satisfy primeval savages such as myself. The Dahlquist DQ-10 is one example which comes to mind.

This confuses me, since I feel that if a speaker system is acknowledged as an accurate reproducer, it should be able to (with the proper electronics) recreate whatever type of music you prefer.

Two possible explanations suggest themselves to me:

1. These reviewers are right, and since any speaker system design is a mass of trade offs, the particular design goals embodied in the product in question make it preferable for symphonic and other such classical music rather than Tom Petty and the Heartbreakers.

Or:

2. These reviewers are wrong and what they are actually suggesting is that a little deliberate distortion in the design could enhance the immediacy and excitement of popular music. I find this idea not entirely repugnant, due to the fact that, as you noted in a previous issue of The Audio Critic, rock-pop music is 'as processed as Kraft cheese' by the time it leaves the studio. Therefore a little additional ''enhancement'" on the listener's end seems hard to condemn. The ideal of course would be an accurate reproducer which is at home with any musical preference.

Your comments please.

Very truly yours, Marc Loos Tampa, FL

We believe that a highly accurate speaker--i.e., wide-range, dead flat, coherent, non-ringing-would be a great success with the rock-pop-disco crowd, provided it could at the same time play very loud with out breaking up. If extra sizzle and boom are indeed what the fans desire (which isn't always true), the effects could at the option of the record producer be mixed right into the master tape and reproduced unaltered through such a speaker. And, of course, accurately recorded classical music would be equally well served by the same design.

The trouble is that, with very few exceptions, accurate audiophile-type speakers can't produce the kind of SPL the rock-pop market demands; furthermore, rock-pop producers rely heavily on loud, inaccurate, sizzle-and-boom monitor speakers to mix the kind of sound they believe will sell. The same mix played through an accurate speaker might not sound punchy enough.

So it's basically a question of whether the fans want fun-house mirrors or genuine pointy-headed fat ladies. The 'production values' will be about the same either way, except that in the first instance you give up the kind of accurate mirror in which the occasional beauties look best.

-Ed.

The Audio Critic:

I read with interest your short article on FM tuners (Volume 2, Number 2), but I feel your "'walking away'' from FM is turning a deaf ear on a tremendous potential: variety.

After all, where else can one hear all this diverse music from which to make his buying decisions? Granted, FM is technically quite poor (my favorite station's turntables make me swear there is an invisible train in my living room), but from the comfort of my apartment, I can listen to classical, jazz, bluegrass, all styles of rock, et cetera, as well as many rare performances of which I could never get a personal copy. This is all leading up to my technical complaint within your review.

Assuming that one wishes to listen to FM (which I feel is a safe assumption), the market is so glutted with FM stations that selectivity becomes a very important factor.

For example, my favorite station, with its unique format to the area, is 80 miles away and 140 watts ERP. Two miles away, approximately 30 degrees off axis, is a 250-watt campus radio station on the adjacent channel playing disco. My landlord would not permit towers in the back yard, nor would he allow horizontally stacked arrays of antennas; two ten-element yagis stacked vertically was the most he would allow. Therefore, I need a tuner with very good adjacent-channel rejection. This is a subject that reviewers in commercial audio magazines seem to ignore, and, unfortunately, you did also. This left me to the whim of manufacturers' published specs and salesmen.

It sure was lucky that I found a store with a two-week take-home test privilege.

Sincerely yours, Fred Rosenberg

West Springfield, MA

Everything you say is undeniably true; we agree with all of it. You must remember, however, that our editorial turf has boundaries; it doesn't extend over the entire do main of electronically reproduced music, at least not at the present stage of our growth.

So far we have concentrated on ''purist'' sound and have walked away from areas where such an outlook seemed hopeless.

That doesn't mean that making the most of a technically bad situation for the sake of music isn't a 100% worthwhile concern. (What about all those priceless old 78's? They can be made to sound much better with a little sophisticated massaging.) We just haven't moved in those directions so far; further more, in the specific case of poor FM sound and chaotic airwave management, we don't particularly wish to reward or encourage the perpetrators by accepting the present mess as a given and exploring temporary band-aid remedies on the receiving end.

-Ed.

The Audio Critic:

Referring back to your 'Admonitor', as I occasionally do for a chuckle or two, I noticed in your admonition of an AR9 ad you make reference to Bjorn Edvardsen's assertion that 'time domain distortions in musical program material are inaudible."' Later, in your praiseworthy review of the NAD 3020, you credit Mr. Edvardsen with designing it.

I agree that the NAD 3020 is a ''sonic'' beauty, and the designer must obviously have a lot on the ball. If he is, in fact, one and the same being, has he thus found the cure, and therefore no longer possesses the disease, or is his disease related only to speaker design? Perhaps the disease isn't all that serious after all, and you just have a touch of hypochondria!

Sincerely, Gerald DeLotto

San Francisco, CA

We just knew that some eagle eye would notice that. The explanation, though, is quite simple. The Audio Engineering Society paper referred to in the Vol. 1, No. 6 'Admonitor' was coauthored by Robert Berkovitz and Bjorn-Erik Evardsen, and we clearly identified both. It just so happens that all the general philosophical ideas presented in that paper came from Berkovitz; Edvardsen, who is no longer with AR, was responsible only for the laboratory measurements and got second billing. We know Bjorn-Erik slightly, have had some technical discussions with him, and are very much under the impression that he believes in the audibility of time-domain distortions. Maybe Karl Marx' s copy editor wasn't a communist, either.

-Ed.

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[adapted from TAC, Vol.2, No.3 ]

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Also see:

Have Tone Arm Designers Forgotten Their High-School Geometry?

Various audio and high-fidelity magazines