Developments in Step-Up Devices for Moving-Coil Cartridges (Vol.2, No.2: 1979)

Cartridge / Arm / Turntable--Briefs and Interim Reports: DB Systems DBP-10 Protractor; Dennesen Geometric Soundtracktor; Denon DA-401; Denon DL-303; Denon DP-80; DiscFoot Isolation System; Fidelity Research FR-14; JVC MC-1; JVC TT-101 JVC UA-7045; Kenwood KD-650; Linn-Sondek LP12 (reappraisal); Ortofon MC30; Thorens TD 115; Wheaton 240 Type 2.

Our promised test of turntable resonances and acoustical breakthrough being delayed once again (for good and sufficient reasons but surely for the last time), we give a few un-postponable items the once-over, until more complete coverage in the next issue.

That's right. The turntable survey we announced two issues ago, with precisely quantified comparisons of mechanical resonances and airborne excitations as measured in various designs, is still far from ready. We're shifting it to the next issue. Our timetable was way off, mainly because of the difficulty of putting a deadline on the solution of unsolved problems. (The last time that was done successfully was in World War II, on the Manhattan Project.) The unsolved problem in this case was the selection of the proper test signal for energizing the turntable environment acoustically. We gradually came to the conclusion that white noise, pink noise, swept sine waves and other standard test signals used by other investigators known to us (see also page 55 of Vol. 2, No. 1) are all grossly unrepresentative of real-world listening room conditions. Actual music, of course, is the most authentic test signal, but it's nonrepetitive and very difficult to extract any kind of steady meter reading or CRT display from. We believe we now have the right test signal, one that models the spectral energy of music correctly and can still be easily dealt with on the lab bench; the rationale will be explained in the next issue in conjunction with the test results. Chalk up this delay to our reluctance to be wrong. We'd rather be late but right.

Meanwhile we're giving below our capsule views on a number of interesting items, so as not to keep you in suspense for another few months. The criteria on which these views are based were explained at some length in the last four issues; here we shall restrict ourselves to the conclusions, which may very well be revised (though in no foreseeable case entirely reversed) after the accumulation of more complete data.

A word about cartridges.

We're also in the process of implementing a realistic laboratory measurement program for phono cartridges, the early results of which will be visible in the next issue. Until then we want to warn you about a totally invalid approach that has only recently emerged from the witch doctor's hut and is beginning to be taken seriously by a few wide-eyed audiophiles. It consists of dropping the stylus of a mounted cartridge on a hard surface, such as glass, and spectrum analyzing the resulting electrical impulse on a Fourier analyzer. The spectral composition of the impulse is claimed to correlate with the audible performance of the cartridge. Since a pickup reproduces music by tracing the groove walls with an indentor, any test method that totally ignores the physics of the stylus/groove interface is of monumental naivete.

Should you ever encounter any cartridge recommendation based on this test, our recommendation is that you start walking rapidly in the opposite direction.

Speaking of the stylus/groove interface, we've been recently exposed to an extremely interesting new experimental stylus design. The diamond tip takes the line-contact idea to its logical limit; the contact area has by far the largest aspect ratio (length to width) ever attempted, extending over almost the entire height of the groove wall. This of course mimics the cutter stylus geometry to the utmost. The stylus beam in which this diamond was mounted had been specially deadened to make it as inactive in terms of energy storage as possible; the cartridge body was that of a standard Japanese low-impedance moving-coil unit--it doesn't really matter which. The whole thing was a preliminary study for a totally

new moving-coil cartridge, which should be out sometime in 1980 and which we were asked, as the price of being privy to this early experiment, not to identify by name. (Please don't write us or call us.) The new cartridge will have a similar stylus, a considerably more sophisticated dead-beam cantilever, and a totally new generator mechanism, unrelated to that of the experimental cartridge we played with. The projected price is $350, but projected prices have a way of going up.

The point is that this rather primitive experimental exercise already sounded better than the Koetsu, which is today's State-of-the-Art moving-coil cartridge! The highs were considerably cleaner and more natural; the midrange was comparable though no better; the output was lower but will be considerably higher, we're told, in the new cartridge.

Overall, the Koetsu sounded slightly “electronic” next to this makeshift hybrid. The designer claims that when the whole act is together and the finished cartridge is released, all other cartridges will become Paleolithic artifacts overnight.

We're always skeptical of such predictions, but in this case we must say there just may be some basis to it. As in loudspeakers, there's a lot of room for progress in phono cartridges. What we now have is far from perfect.

DB Systems DBP-10 Protractor

DB Systems, PO Box 187, Jaffrey Center, NH 03454. DBP-10 Phono Alignment Protractor, $19.95.

This isn't much more than a very durable and precise version of the homemade cartridge/arm alignment protractor we described on page 47 of Vol. 1, No. 6. It's made of thick, tough plastic; it has various useful auxiliary lines and grids printed on both sides; in addition, it comes with a transparent plastic overlay printed with markings that permit you to hunt for the correct overhang without having to swing the cartridge all the way over the spindle. The principle of the DBP-10 is that if the cartridge is in perfect alignment at both of the two zero-error radii, then the overhang is automatically correct. There's nothing wrong with this approach, except "that we don't find it a hardship to measure the overhang directly. Of course, there are some situations where it's impossible to swing the arm further in than the lead-out grooves. In any case, this is a very neat and convenient way to have a permanent alignment protractor, correctly calibrated. Highly recommended.

Dennesen Geometric Soundtracktor

Dennesen Electronics, PO Box 51, Beverly, MA 01915. Geometric Soundtracktor, $35 in plastic, $100 in aluminum.

A more ambitious and elaborate gadget than the above, the Dennesen makes use of a clever geometrical insight to make possible correct lateral tracking alignment in one shot, with a single adjustment.

The design is based on the fact that, when the alignment is correct for standard LP records, the product of the effective arm length and the sine of the offset angle is always 93.4 mm, regardless of the arm used. If you set up a right triangle such that its hypotenuse is the line from the arm pivot to the inner zero-error point, at a radius of 66.0 mm, and its shorter side is an extension of that radius through and past the turntable spindle by an additional 27.4 mm for a total of 93.4 mm (66.0 + 27.4 = 93.4), then your lateral tracking geometry is locked in; all you need is perfect tangential alignment at that one zero-error point. The Dennesen is a precision tool that enables you to do this very conveniently, in a matter of minutes-but there's a hitch. If you don't locate the lateral pivot point of the arm right on the button, all bets are off. The final alignment could then be grossly in accurate in certain cases, even if you performed all subsequent steps perfectly. This isn't just nit-picking, since the exact pivot point is often very hard to determine from the top.

It would have been much better to extend the base plate of the tool another couple of inches in order to include the outer zero-error point as a verification check. There's safety in redundancy. (The extra accessory Dennesen does give you, instead, is a rather awkward VTA indexer, which is supposed to help you come back repeatedly to the correct VTA for a particular record, once you have found it by ear. All we can say about it is that it's primitive but harmless.) Incidentally, the 'pat. pending' legend on the Geometric Soundtrack raised some eyebrows in our circles. Is Dennesen trying to patent a mathematical truth? It won't be a very strong patent in that case, even if the patent examiner doesn't quite understand the subject and agrees to everything. As a well-made and handy tool, however, the device has our complete approval-as long as you know exactly where the arm pivot is located.

Denon DA-401

American Audioport, Inc., 1407 North Providence Road, Columbia, MO 65201. Denon DA-401 Integrated Tone Arm, $360. Tested sample on loan from importer.

A handsome and beautifully made carbon-fiber tonearm, the DA-401 has slightly wobbly bearings and no provision for adjusting the VTA during play. At this stage of the game, that's not what is expected of a $360 arm. Too bad, especially since the geometry is almost 100% correct (though not the overhang instructions) and the antiskating mechanism particularly nice.

Denon DL-303 (interim report)

American Audioport, Inc., 1407 North Providence Road, Columbia, MO 65201. Denon DL-303 Moving Coil Cartridge, $385. Tested sample on loan from importer.

Our initial impression of the new top-of-the-line Denon cartridge is that it isn't as good as their older DL-103D, which in turn is several small steps below our current recommended choices. See final review in the next issue.

Denon DP-80 American Audioport, Inc., 1407 North Providence Road, Columbia, MO 65201. Denon DP-80 Quartz Locked Turntable, $960 (complete with required voltage step-up transformer). Base, $690. Tested sample (without base) on loan from importer.

This is the top-of-the-line Denon with the big motor we briefly referred to on page 59 of the last issue, in anticipated comparison with the Technics SP-10 Mk II. Well, now we know that the DP-80 doesn't have quite as much torque as the SP-10 Mk II, but in the Cotter B-1 base it certainly works just as well and sounds just as good. We still consider the magnetic tachometer system of the Denon direct-drive turntables to be a bit fragile and fussy, though certainly superbly accurate, and we still like the brute-force brake system of the SP-10 Mk 11 better; on the other hand, the latter seems to be much more difficult to obtain these days and the Denon isn't in any way inferior in performance. The DP-80 has no third speed, though, and on U.S. voltages it only works with the accessory step-up transformer. (Not enough demand for a separate U.S. model.) Our verdict for the moment: SP-10 Mk II for anvil-like utility; DP-80 for electronic sophistication; either one in the Cotter B-1 base for the ultimate in sonic accuracy.

The factory bases are another matter altogether.

DiscFoot Isolation System (interim report)

Discwasher, Inc., 1407 North Providence Road, Columbia, MO 65201. DiscFoot Turntable Isolation System, $22 (four feet). Additional feet, $5.75 each. Tested samples on loan from manufacturer.

We' ve made fun in the past of the little rubber nipples and ineffectual pillboxes most turntables stand on. Well, the DiscFoot is better, though not all that different in physical appearance. Just how much better will become clear when we complete our turntable resonance tests; you can expect a full report in the next issue.

Meanwhile, we can tell you that the DiscFoot system won't appreciably lower the resonant frequency of the turn table suspension, so it can't provide additional isolation at the lowest frequencies. Nor can it protect in any way against airborne excitation. What it can do is to lower the Q of system resonances in a somewhat higher frequency range, thereby isolating certain kinds of mechanical feedback and footfall vibrations. It does this as a result of the chemical/physical properties of the material it's made of. Very interesting and definitely deserving of further attention.

Fidelity Research FR-14

Fidelity Research of America, PO Box 5242, Ventura, CA 93003. FR-14 Precision Tone Arm, $400. Tested #011187, on loan from distributor.

This is an arm of the same length as the FR-64s and made with the same tender loving care. Everything about it is simply gorgeous, including the bearings. It isn't dynamically balanced, however, like the FR-64s, nor does it have provisions for VTA adjustment during play. At $400, that begins to look like a not particularly good buy in this age of VTA enlightenment, especially in comparison with the much cheaper JVC UA-7045 (see below).

JVC MC-1 (interim report)

US JVC Corp., 58-75 Queens Midtown Expressway, Maspeth, NY 11378. MC-1 Direct Couple Type Moving Coil Cartridge, $300. Tested #10300174, on loan from manufacturer.

The final, full production version of this cartridge has none of the irritating high-frequency coloration we reported in our review of the prototype on page 45 of Vol. 1, No. 5.

The highs are smooth and pleasant; the overall sound is very clean and transparent. If it weren't for the $230 Fidelity Research FR-1 Mk 3F, we wouldn't hesitate to rate the MC-1 as by far the finest moving-coil cartridge in its price range.

The FR, however, appears to us to have even greater mid range clarity, approaching that of the Koetsu, and also a more completely neutral character. This may not be a final verdict, since our exposure to the JVC was somewhat limited. See the next issue for a more thorough evaluation.

JVC TT-101 (interim report)

US JVC Corp., 58-75 Queens Midtown Expressway, Maspeth, NY 11378. TT-101 Direct Drive Turntable, $1000 (with base).

JVC's answer to the Denon DP-80 and the Technics SP-10 Mk II came to us so close to press time that we couldn't even set it up and listen to it, let alone test it for real. We do want to tell you, however, that the construction and craftsmanship are of the highest order, as in other top-of-the-line JVC 'Laboratory' products. Big motor, lots of torque (though not quite as much as in the SP-10 Mk II), two speeds, very elegant speed control with 13 discrete and repeatable steps-these are the immediately apparent features even be fore actual use. We see nothing in this unit that would obviously prevent it from being the best of them all, but only the full test will tell. The factory base, on the other hand, is totally pedestrian; the Cotter treatment is definitely called for.

JVC UA-7045 US JVC Corp., 58-75 Queens Midtown Expressway, Maspeth, NY 11378. UA-7045 Tone Arm, $250. Tested #12405142, on loan from manufacturer.

We're simply delighted with this well-designed arm, which looks to us like the nearest thing to a Fidelity Research FR-64s, at a fraction of the price. Maybe it isn't quite as beautifully constructed but it's close, and it's extremely convenient to set up and to use. It lacks dynamic balancing, to be sure, but the bearings are nice and tight, the arm tube doesn't ring, the antiskating bias adjustment is a cinch, and-surprise, surprise!-the VTA is tunable during play.

All that and a very dead magnesium headshell, too-what more can you ask for $250 in this day and age? We'll call this one Reference A Minus.

Kenwood KD-650 (interim report)

Kenwood Electronics, Inc., 1315 East Watsoncenter Road, Car son, CA 90745. KD-650 Direct-Drive Turntable, $400 (with arm). One-year warranty. Tested #960133, on loan from manufacturer.

This is an improved version of the Kenwood KD-500 turntable that was our original 'Reference B' recommendation. The main improvement is the quartz-locked direct drive: the ''resin concrete'' chassis is similar and, though not totally inactive acoustically, a lot heavier and deader than the resonant tin cans you generally get at this price: the workmanship and finish appear to be better; and the tone arm that comes with the KD-650 version (the armless version, KD-600. costs $50 less) is surprisingly sophisticated in design, with very convenient though limited-range VTA adjustment during play. How about that? We detected a very small amount of wobbly ''give'' in this arm, but it doesn't seem to come from the bearings. The probable culprit is the setscrew holding the arm pillar in the sleeve; this is a curable disorder that will be dealt with in our final review.

The main fault of the KD-650 is once again that it has no suspension to speak of, relying almost entirely on its inertial mass for isolation. A Cotter B-2 isolation platform would be a great addition, making it a $595 system complete with arm, which is still within 'Reference B' range, though just barely. Even so, we don't know of anything better for the money.

Linn-Sondek LP12 (reappraisal)

Linn Products Ltd., Glasgow, Scotland: distributed in the USA by Audiophile Systems, 5750 Rvmark Court, Indianapolis, IN 46250.

Linn-Sondek LP 12 Transcription Turntable, $865. Two-year warranty (electrical components one year). Tested #019794, on loan from distributor.

Our candid avowal that the main bearing of our original test sample hadn't been filled with oil (see Vol. 1, No. 6, p. 56) stirred up a full-scale tempest in the small but steamy teapot of Linn-Sondek groupies. There's something about an audiophile-oriented product having some technical merit but also some very basic flaws (Magneplanar is another example) that engenders a highly defensive cultism among its sellers and buyers. They'll tell you that if you're experiencing the flaws, you're doing something terribly wrong-be cause the product is well-nigh flawless. Doing everything right involves a whole series of rituals, all of them having to do with second-order and third-order effects and designed to draw your attention away from the first-order defects. For example, the U.S. distributor of the Linn-Sondek told us that we mustn't mount our cartridge with anything but steel screws and nuts because other metals don't provide enough rigidity and alter the sound. What he didn't tell us, on the other hand and among other things, was that the Linn Sondek's tinny little subchassis holding the platter, main bearing and arm board is acoustically so live that you can twang it like a banjo. Some perspective! No wonder this crowd went into a paroxysm of I-caught-you-red-handed when they read about the bearing oil.

Now anyone who isn't completely untutored in the fundamental technical disciplines would grasp immediately that the amount of oil in the bearing well isn't a vital, all-or-nothing link in the complex mechanical system that couples the stylus to the groove in motion. It represents a teeny-weeny fraction of the total slack and wobble in the system, unlikely to have an influence on audible effects significantly above threshold. That indeed turned out to be the case when we retested the turntable; the consensus was that the difference was either inaudible or so small as to be uninteresting even to the purist. Of course, once the vial of oil was added, it was impossible to A-B back and forth between the two conditions for further verification. It should also be remembered that there's always quite a bit of lubrication in the bearing well as the turntable is delivered from the factory; we never tested a totally dry condition. The whole thing was an exercise in techno-fetishism.

In fact, our reexamination of the Linn-Sondek actually lowered our opinion of it in a number of respects. We've already mentioned the liveness of the mounting plate; both the Cotter and the Win systems are incomparably deader.

Another problem is that the drive belt can be sufficiently displaced by violent low-frequency excitation of the suspended system to cause audible modulation of the sound. All you need is a piano record with thunderous bass, a pair of really good subwoofers and a fairly resonant floor. Compared with the Cotter B-1, for example, the Linn-Sondek will occasionally sound a little dithery under these circumstances.

There's no substitute for high mechanical impedance, i.e., large inertial mass. (See also our original review in Vol. 1, No. 5 for the various disadvantages of small mass cum soft springs cum high Q.) Add to all this the lack of 45 RPM, lack of speed control, lack of first-rate appearance and finish except for the moving parts, and the new price of $865 will begin to look like a rip-off. What it buys is, after all. not much more than a glorified AR turntable.

A few users have tried to improve the Linn-Sondek by immobilizing its suspension, putting it on a Cotter B-2 isolation platform, and burying all un-deadened structures in sight in gobs of Duxseal. At that point you've got one hell of an ugly $1060 turntable that's a lot less active mechanically and acoustically. You've also got a whole new set of enemies, including the manufacturer, the distributor and most dealers of the Linn-Sondek. Our impression is that these people can't deal with technical criticism and scientifically enlightened debate; their response is a mystical assertion of unarguable superiority and a pitying condescension toward incompetents holding contrary opinions. You can experience it at shows and read about it in various printed bulletins. The Linn Sondek is the theocratic turntable.

Ortofon MC30 (interim report)

Ortofon, 122 Dupont Street, Plainview, NY 11803. MC30 Moving Coil Cartridge, $600. Tested #841895, on loan from manufacturer.

Our biggest disappointment in cartridges so far, especially after the tantalizing comments made about it in our State of the Art seminar (see Vol. 2, No. 1, p. 33). The initial listening tests gave evidence of considerably less clarity and more noticeable colorations than we heard with much less costly MC cartridges in our reference system, such as the FR-1 Mk 3F, the JVC MC-1 and the GAS 'Sleeping Beauty' Shibata. We seriously doubt that this conclusion will be reversed by our more probing investigations to be reported in the next issue, but we sure hope so. This is no $600 cartridge the way we see it now.

Thorens TD 115 (interim report) Elpa Marketing Industries, Inc., Thorens and Atlantic Avenues, New Hyde Park, NY 11040. Thorens TD 115 Semiautomatic Turn table, $450 (with integral arm). One-year warranty. Tested #12477, on loan from manufacturer.

We expected ''Reference B'' quality from Thorens at this price, but no such luck. The chassis is of the resonant tin-can school; the suspension is of highly questionable de sign, with insufficient travel; the entire structure is light and flimsy; and-horror of horrors-the arm is shock-mounted in such a way that the tracking geometry can be modulated during play. The whole concept reflects a total disregard of the basic physics of phono reproduction and a preoccupation with nonessentials. Maybe our quantitative tests will mollify this harsh judgment, but our ears certainly don't. Where's that old Thorens know-how?

Wheaton 240 Type II

Wheaton Music, Inc., 2503 Ennalls Avenue, Wheaton, MD 20902. Model 240 Type II Decoupled Precision Tone Arm, price NA. Tested sample on loan from manufacturer.

Herbert Papier, an affable gentleman who comes from the watch-making discipline and is now the proprietor of Wheaton Music, has been after us for almost two years to say something about his handcrafted tone arms. They're very precisely made, with a great deal of attention to mechanical detail, though not necessarily with a total systems view of the phono arts.

The first Wheaton arm we saw was a Rabco SL-8E modification, incorporating some very sensible mechanical improvements; it had a hollow balsawood arm, however, with a characteristic midrange coloration that could be evoked by tapping and was also audible in the music.

Regardless of that, we don't consider the basic Rabco con figuration, which requires virtual disassembly for height adjustment, to be a viable arm in this new era of tunable VTA.

The current Wheaton 240 Type II arm is a pivoted design of correct geometry and a larger range of VTA adjustment during play than is available in any other arm known to us. The design comes off as a bit Rube Goldberg-ish, with too many parts sticking out in too many places, but they're all beautifully machined and work very well. Among other things, the antiskating bias can be disabled during cueing-a very nice touch. Again, the Achilles' heel of the arm is the same square-cross-section, hollow balsawood design of the arm tube, which is much too live and has the same sonic signature when tapped-and, of course, when playing the record. Obviously, the lighter-is-better fallacy has been working overtime here. A more useful precept for guiding Mr. Papier's skilled hand would be that the only good tone arm is a dead tone arm.

Recommendations

Things seem to be moving more slowly in this product category than in others, as the familiar faces below will attest.

Best phono cartridge in actual production, regard less of price: Koetsu.

Close to the best at a very much lower price: Fidelity Research FR-1 Mk 3F.

Best tone arm, regardless of price: Fidelity Research FR-66s (if you have the room for it) or Fidelity Research FR-64s with B-60 stabilizer.

Close to the best at a very much lower price: JVC UA-7045.

Best turntable, regardless of price: Cotter B-1 sys tem with specially adapted Technics SP-10 Mk II or Denon DP-80.

Best turntable/arm per dollar: Kenwood KD-650.

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[adapted from TAC]

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Also see:

Diamond Styli for True High-Fidelity Reproduction -- By Dr. Sao Zaw Win, Win Laboratories, Inc.

FM Tuners: A Hopeless Dilemma for the Serious Audio Reviewer: NAD 4080; Sequerra Model 1; Series 20 Model F-26; Yamaha CT-7000

Why We're So Mean, Vindictive, Arrogant, Negative--and Truthful

Various audio and high-fidelity magazines