The Cartridge/Arm/Turntable Scene: Credible Improvements at Incredible Prices (Vol. 2, No. 3, Spring - Fall 1980)

The Cartridge/Arm/Turntable Scene: Credible Improvements at Incredible Prices -- EON POD Disc Clamp, Fidelity Research MC-201, JMAS MIT-1 ; Platter Matter , Win Laboratories SDC-10, SDA-10, SDT-10-2 and SPG-10.

You can plug a complete, matched and at least partly SOTA phono system into your power amplifier for $4915, or you can have a truly excellent moving-coil cartridge (probably the best) for ''only'' $325.

First, an admission of temporary bafflement. We're stymied. Having postponed our comparative test report of mechanical resonances and acoustical breakthrough in turn tables and tone arms for two issues in a row (and far-apart issues at that), we were absolutely certain we could publish meaningful results in this issue. We were wrong. What we had thought was the right track, leading to a satisfactory correlation between measurable and audible characteristics, turned out to be booby-trapped. We ran into some major surprises.

A brief explanation is in order, although it may not satisfy those who, for their $30 subscription, expect us to know and do what nobody else has ever known or done. As we've said a number of times before, we try to do our homework a little better than other audio reviewers, but creating new knowledge that simply wasn't there before is another matter. You can't schedule it to happen.

How the resonance tests lost their relevance.

Those who do their homework at least don't end up sweating over problems already solved by others, so we studied carefully the best investigative efforts that had preceded our own. The most germane of these seemed to be the work of Poul Ladegaard, one of the top audio researchers at the Bruel & Kjaer instrument company (his 1977 Audio Engineering Society paper, '' Audible Effects of Mechanical Resonances in Turntables'', while indirectly promoting B&K instruments, is an excellent analytical survey of the subject) and of Martin Colloms (in the English Hi-Fi Choice series, where he was responsible for the 'Turntables & Tonearms'' volumes both in 1978 and 1980). These gentlemen had done such a competent and complete job that we felt we could make a further contribution in only two major respects:

applying their tests to considerably more exotic and costly turntables than they had measured, such as the Cotter B-1 system and the Win SDC-10, and using an acoustical excitation signal more closely modeled on the spectral energy of music than the pink noise they had relied on. With the aid of a complex waveform synthesizer, we experimented with signals in which all the low-frequency energy was concentrated at only a limited number of amplitude peaks per octave, as in the bass octaves of actual music, and we made an attempt to contour these signals to correspond to the Robinson-Dadson equal-loudness curves. Such a ''musically'' structured sound field creates vastly more severe conditions of mechanical and airborne excitation than pink noise and can be expected to show greater differences in acoustical activity between various turntable designs.

We were getting some interesting results with these experiments when two separate and unrelated observations shook us up to the extent that we began to doubt our basic assumption-namely that the resonances we were testing constituted the main difference in audible quality among turntables that were otherwise sub-threshold in rumble, wow, flutter and other traditional specifications. The first surprise was the Platter Matter turntable mat (see review below), which for $35 could effect a greater sonic improvement in some cases than switching to a more sophisticated turn table/arm design. Apparently the isolation and damping of the vinyl disc can under certain circumstances be more important than all the other elaborate and costly isolations and dampings put together. The second and even bigger surprise was the much more transparent and uncolored sound we got out of our reference MC cartridge (the Fidelity Research MC-201) when we installed it in the Win SDA-10 arm mounted on the Win SDC-10 turntable, after having listened to it for many weeks in our super-isolated and super-damped Cotter B-1 reference table with Technics SP-10 Mk II motor, FR-66s arm and Platter Matter! Obviously, it wasn't still better isolation and still better damping in the Win system that made the difference. As a matter of fact, we ended up actually measuring what might have been at least one genuinely relevant difference, a strange once-per-revolution peak of approximately 10 dB amplitude in the left-to-right channel crosstalk of every cartridge measured in the Cotter system but not the Win-always with the same test record, same sample of each cartridge, same B&K measurement setup, same everything! That did it. We decided to reconsider the entire project and to withhold our conclusions, whatever they might turn out to be, until the publication of The Audio Critic Handbook. That doesn't mean we won't be auditioning and measuring turntables, arms and cartridges. On the contrary, we're up to our neck in them just now. But we'll be going easy on the theory for a while. To quote the Ladegaard paper, "'here is an area which, at present, has rather poor correlation between the measurement methods available and the impact on the sound quality." You said it, fella.

Our phono cartridge tests.

We've begun what we hope will turn out to be an exhaustive survey of high-quality moving-coil cartridges, encompassing all their measurable and audible characteristics. We're using the complete set of B&K test instruments designed for this purpose, along with test records of many different makes, plus of course our Reference A system for listening. When the survey is complete, our summarized findings will be published in the form of a large foldout chart in one of our forthcoming biweekly Bulletins.

So far we've screened and have at least a qualitative opinion on the following cartridges, out of which those that stood out unequivocally in our initial tests are being fully reviewed below. That doesn't mean the others are unworthy of consideration; on the contrary, this is on the whole a very superior group:

Denon DL-303 ($385), Dynavector DV/Karat Ruby (8275), Dynavector DV/Karat Diamond ($1000), Fidelity Research FR-1 Mk 3F ($230), Fidelity Research MC-201 (8325), JMAS MIT-1 ($550), JVC MC-1 ($300), Koetsu ($750), Ortofon MC30 ($650), Signet MK111E ($300), Supex SDX-1000 ($500).

Unfortunately, that $350 super cartridge with all-new technology, the possible 1980 debut of which we had some what imprudently projected in the last issue, just hasn't happened. It may very well end up as a drawing-board exercise, as far as we can tell at this point. The experimental hybrid we discussed in the same context can now be revealed to have been a Coral 777 from Japan with aluminum cantilever, modified to incorporate an early version of the remark able Van den Hul stylus. The JMAS cartridge reviewed below is a rather similar design, with beryllium cantilever and the latest Van den Hul diamond.

EON POD Disc Clamp EON Research & Development Corporation, 285 West 39th Avenue, Vancouver, BC, Canada V5Y 2P4. POD Disc Clamping De vice, price NA.

This simple little three-legged plastic clamp slips on your turntable spindle, grabs it tight and applies pressure to the label area of the record at three points. This immobilizes the record and welds it to the platter/mat mass just as successfully as heavy turntable weights (like the Pyramid RW-1 we reviewed two issues ago), without putting an extra load on the turntable bearing. Of course, the additional mechanical grounding provided by the extra mass of a turn table weight isn't available with the featherweight POD, but in combination with a sticky and highly dissipative mat like the Platter Matter the POD works like a charm, creating a vacuum under the record with a very strong hold-down grip and helping the mat do its job of damping acoustical activity in the vinyl. Highly recommended.

Fidelity Research MC-201 Fidelity Research of America, PO Box 5242, Ventura, CA 93003.

MC-201 moving-coil cartridge, $325. Tested #1A, on loan from distributor.

This stubby little blue cartridge became our absolute favorite after about 20 seconds of listening. Its totally sweet, smooth, edgeless quality, combined with delicacy of detail and fast response to transients, plus transparency of the most natural, believable sort, all help to disarm the most hard nosed critic. Perhaps the IMAS MIT-1 cartridge reviewed below extracts even more information from the groove with even greater resolution (probably because of the difference in styli-Van den Hul in the MIT-1, a somewhat more moderate line-contact tip in the MC-201) but it sounds a little harder, zingier and ultimately less musical than the Fidelity Research.

The distinguishing features of the MC-201 are the avoidance of iron or other magnetic material in the coil core and the very short, light cantilever, which is made (at least as far as we can tell) of mundane aluminum. In our experience, aluminum cantilevers are acoustically deader and therefore more neutral in sound than those made of stiffer * 'high-tech' metals. Our measurements showed that the characteristic HF peak of the MC-201 is at 30 kHz, a much higher frequency that is typical, and that its response is especially flat in the critical 100 Hz to 6 kHz range. The impedance of the cartridge is approximately 10 ohms; its voltage output is relatively low, requiring the use of a fairly high-ratio step-up trans former. (We're using the Cotter MK-2L.) Justin case you desire a second opinion confirming our own, the Mobile Fidelity Sound Lab people have told us that they had screened an even larger number of moving-coil cartridges than we did and came up with the MC-201 as their top choice for monitoring the quality of their “original master recordings." And their phono cartridge budget isn't limited to $325, as you can well imagine. We rest our case.

JMAS MIT-1 John Marovskis Audio Systems, Inc., 2889 Roebling Avenue, Bronx, NY 10461. Mirror Image Transducer MIT-1 moving-coil cartridge, $550. Two-year warranty (excluding mishandling). Tested #1008, on loan from manufacturer.

The first high-end production cartridge to incorporate the widely acclaimed Van den Hul stylus, the MIT-1 quickly became part of our reference system on its sonic merits, only to be ultimately replaced by the Fidelity Research MC-201.

The MIT-1 possesses the highest transparency and definition of inner detail among the cartridges known to us, but it also has a harder and brighter character in the treble range than we consider desirable, though far worse examples of the same problem could be cited at equally high prices. The sad fact is, however, that we've never encountered a cartridge with a beryllium cantilever such as this one that didn't have pretty much the same signature. If it weren't for that one shortcoming, the MIT-1 would still be our reference cartridge. It appears to extract more information from the groove than any other.

That capability is almost certainly due to the Van den Hul stylus profile, which corresponds more closely to the geometry of the cutter stylus itself than any other configuration available so far. The stylus actually touches about 80% of the groove wall with its extremely tall and narrow areas of contact. This makes all alignments unusually critical, both in the manufacturing process and in the installation of the cartridge in the tone arm. Stylus orientation in the cantilever, azimuth angle and tracking angles must all be right on the button. When everything is trimmed in to the nth degree, the maximum benefits in tracing, groove noise reduction, dynamic range and separation will be realized--and they're quite spectacular. Only a single firm in Switzerland makes the Van den Hul stylus, which is named after its Dutch inventor; the unique profile magnifies all the usual manufacturing problems, such as crystallographic orientation of the diamond, symmetry, finish, etc., and the rejection rate is therefore higher than usual. An improperly made and/or mounted Van den Hul tip will recut the groove; there's no margin for error. But when it works, it really works.

Our measurements showed that the rising characteristic of the MIT-1 starts at about 11 kHz, up to which point the response is dead flat. The high-frequency peak of 4 to 5 dB is at approximately 22 kHz. Channel separation is quite excellent. In fact, everything about the cartridge looks good on the lab bench. This is a design which is still in the evolutionary stage; right now the innards of the cartridge come from Coral, as did the GAS Sleeping Beauty's, but the concept isn't restricted to that particular system, and we have a feeling that an even finer design will emerge from this auspicious beginning.

Platter Matter Platter Matter Inc., 792 Millwood Road, Toronto, Ont., Canada M4G IW2. 'Platter Matter' turntable mat, $34.95. Tested sample on loan from manufacturer.

This isn't the first high-priced, super special turntable mat to cross our path, as you can undoubtedly surmise, but it's the first one we've found interesting enough to review.

Not that we intend to open the whole can of worms about the theory and correct design of turntable mats. That belongs with our discussion of mechanical resonances and acoustical breakthrough in turntables and arms, which as we've already said is under reconsideration until the publication of our Handbook. Meanwhile every available opinion on the subject contradicts every other: Martin Colloms in Hi-Fi Choice No. 18 comes out in favor of glass mats (but uses a comparative measurement technique we find less than impeccable); the Trio-Kenwood engineers in Japan point out the inadequacies of glass and opt for sintered alumina ceramic impregnated with silicone rubber; the French and the Canadians are gung ho for soft and sticky mats made with zinc oxide-shall we go on? We don't know of a single analytical study that covers all bases and coordinates the multiple causes with the multiple effects. (Don't look at us, buster.) That said, we must state that the Platter Matter really works. It's of the soft and slightly tacky zinc-oxide treated variety, designed to weld itself to the record, especially when the latter is pressed down into it with a clamping device like the EON POD. The dissipative composition of the mat isolates the vinyl and terminates standing waves and random vibrations init very successfully. The result is audibly greater clarity and delicacy of inner detail in the playback, with lowered background hash and a feeling of firmer control overall. We were quite amazed, especially since the difference the Platter Matter made was in some cases greater than switching to a turntable of more advanced design. It seems to be the aspirin for assorted audio headaches, available without a prescription.

About the only fault we can find with the Platter Matter (other than its not particularly attractive greenish-blue looks) is actually a virtue: it sticks to the record too well. The vacuum it creates is hard to break and the mat comes off the turntable along with the record. You literally have to peel it off. The life of the dedicated audiophile is not an easy one.

Win Laboratories SDC-10, SDA-10, SDT-10-2 and SPG-10 Win Laboratories, Inc., PO Box 332, Goleta, CA 93017. SDC-10 Reference Transcription Turntable, $2925. SDA-10 Servo Dynamic Arm, $1000. SDT-10-2 Semiconductor Disc Transducer with Power Source, $595. SPG-10 Switching Passive Gain Control, $395.

Tested samples on loan from manufacturer.

This is it-the complete Win front end, a matched system for phono playback (plus passive switching of other program sources), ready to plug into any power amplifier at line level, without the need for a preamplifier. All you pay is $4915; absolutely nothing else to buy. And it looks like nothing else in the whole world: thick transparent plastic and sculptured metal with a high polish, sexy-looking little rods and levers, even a padded satin coverlet to keep it comfy when it sleeps-everything it takes to trigger the I've Got-to-Have-It syndrome.

Does it sound as good as it looks? Well, the turntable and tonearm are now in our Reference A system. The phono cartridge is a very special case that has to be discussed separately. Our overall reaction to the system as a complete front end was instant recognition of its superior transparency and sheer you-are-there realism, followed by the realization that part of the transparency was due to the elimination of a multistage voltage amplification chain and that the SDT-10-2 strain-gauge cartridge still had some problems. Let's take each component one by one.

SDC-10 Turntable The changes incorporated in this ''final'' version (if, indeed, anything conceived by the restless mind of Sao Win is ever final) as compared with the very early sample we reviewed two issues ago include a slightly revised suspension (lower Q, less jittery), a much finer motor, a new mechanical stop under the main bearing housing to facilitate the tightening of disc clamping devices, and a number of subtle improvements in the already exquisite appearance of the product. The basic concept remains the same: seismic platform with self correcting three-point suspension, relatively low-torque DC motor with high inertia, belt drive, heavy platter with high moment of inertia, three concentric ' 'wave trap'' rings (so called by Dr. Win) embedded in the platter in lieu of a mat, fanatical attention to materials, friction and tolerances.

Does the SDC-10 offer the same degree of isolation from extraneous mechanical excitations as the Cotter B-1? Obviously not (although our initial exploratory measurements were somewhat inconclusive). A truck and a sports car, even if their suspensions were tuned to the same frequency with the same Q, wouldn't be equally isolated from potholes in the road, either. A larger mass, having higher inertia, is always more immune to outside shocks, all other things being equal.

Furthermore, the metal-and-plastic laminations of the Cotter base and arm pad are definitely more dissipative (i.e. , deader) than the leaded plexiglass used in the Win. The question is, how much isolation and damping do you need? Under the most severe conditions of actual use in a music system, the SDC-10 appears to be impeccable in those respects. It does the job, as well as the job needs to be done, without the penalties of overkill (such as unmanageable weight and the agricultural machinery look). Dr. Win is the only turntable designer known to us who has access to a government laboratory facility where a shaker table and a whole bank of simultaneously operating spectrum analyzers are available.

Accelerometers attached at many points to the turntable, each with its own spectrum analyzer readout, can be used to determine the vibrational characteristics of a design under development. Tools like that made it possible to design the SDC-10 as a balanced system with correctly matched working parts, of which the SDA-10 arm was also calculated to be one. The whole effort reflects a systems approach to the realization of a desired level of performance, rather than just a let's fix-it job to swamp all possible resonances with a mechanical sink.

What do we now think of belt drive vs. direct drive? We suspect that the superiority of the Win system isn't so much due to the way the drive happens to be applied to the platter but rather to the flawless dynamic characteristics of all the rotating parts: platter, main bearing, motor, pulley. A direct-drive system made with the same fanatical care would provide the only fair comparison. (See also our Win vs.

Cotter/Technics/FR discussion in the preamble to these re views.) SDA-10 Arm This is entirely new and entirely delightful. It com bines in a single design everything we liked about the Breuer Dynamic and the FR-64s/66s, our last two reference tone arms, and a great deal more.

The outstanding design feature of the SDA-10 is the use of two opposed ring magnets of repellent polarity to suspend the entire weight of the arm, permitting the use of relatively fragile sapphire jeweled bearings in the gimbals to achieve virtually frictionless vertical and horizontal movement. In addition, the magnetic suspension creates a mechanical servo effect that stabilizes and damps the arm. Vertical tracking force is applied by means of an exceptionally high quality spring mechanism, the arm being dynamically balanced (as are the Breuer and the FR). The excellent outrigger antiskating device can be disengaged by means of a clutch for easier nulling of the static balance. Best of all, the vertical tracking angle (VTA) is continuously adjustable over a range that, for once, we find sufficient for just about all modern LP's. Yes, the SDA-10 is a joy to use.

The headshell of the arm is not of the universal plug-in type; Dr. Win doesn't trust the mechanical integrity of that arrangement, which has the further disadvantage of not permitting even the slightest rotation for azimuth adjustment.

The fixed headshell of the SDA-10 can be loosened with a small screwdriver and turned (or even moved longitudinally), although this is not recommended to heavy-handed owners.

The cartridge mounting holes are drilled only for the Win SDT-10-2, since the arm was designed primarily to work with that cartridge, but a more universally adaptable shell is supposed to be coming out soon. Meanwhile we've found it possible to mount other cartridges in the arm by using smaller screws that allow some play in the holes.

In fact it was our experiments with other cartridges, especially the Fidelity Research MC-201, that made us come to our conclusion about the superior transparency, definition and freedom from thickish colorations of the total Win sys tem versus the Cotter/Technics/FR combination (our previous Reference A record player). We have a hunch that the SDA-10 arm contributed more to that difference than the SDC-10 turntable, although the measured anomalies in the Cotter system that we discussed above probably came from the Technics motor.

SDT-10-2 Cartridge with SPG-10 Control

The conceptual beauties of the Win strain-gauge de sign have already been dwelt on at some length in Vol. 1, No. 6 and Vol. 2, No. 1; here we intend merely to give a progress report on this constantly evolving product. Its latest avatar incorporates a sapphire cantilever with Vital stylus (made by Ogura). We tested two samples, which were quite similar but not identical in measurable and audible characteristics. Their power source modules were also slightly different; the second module had the newer IC chips currently used in the production version. Both cartridges exhibited a bass boost: 6 to 7 dB at 20 Hz in the first sample, 4 dB at 20 Hz in the second sample. (The fundamental resonance of the arm/ cartridge combination was at about 16 or 17 Hz.) Both samples had a 5 to 6 dB treble peak at a surprisingly low frequency: 9 kHz in the first, 7 kHz in the second. The first sample came back to full passband level after the dip that followed the peak, staying there up to 27 kHz; the second only came back within -3 dB of the passband. The first sample had incredibly poor separation (9 dB to 13 dB); the second was a little better (14 dB to 19 dB).

These are somewhat disturbing, indeed discouraging measurements, indicating still unsolved problems in the transducer structure and the internal (mechanical) RIAA equalization. The sound, however, turned out to be startlingly trans parent, detailed and focused, with a reach-out-and-touch-it kind of immediacy. Part of that was undoubtedly due to the elimination of the preamp from the audio chain (the SPG-10 control unit is entirely passive), but the speed and signal-path simplicity of the strain-gauge transducer must have had some thing to do with it. Only after several minutes of listening did the coloration introduced by that top-end peak become annoying and, eventually, unacceptable. The first sample actually sounded more musical, with airier highs, but the poor separation resulted in a quasi-mono effect. The rising bass in both samples was audible but not annoying. And that's about the size of it-until the next modification. The ultimate refinement of this remarkable device should be worth waiting for.

Recommendations

This time it's a whole new ball game.

Best phono cartridge, regardless of price: Fidelity Research MC-201.

Best phono cartridge per dollar: Fidelity Research MC-201.

Best tonearm, regardless of price: Win Laboratories SDA-10.

Best turntable, regardless of price: Win Laboratories SDC-10.

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

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

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Also see:

Moving-Coil Step-Up Roundup: Audire 'Poco' , Fidelity Research FRT-3G , Nagatron Ag 9200; PS Audio (interim report) , RWR Audio MCT-1 (follow-up)

Various audio and high-fidelity magazines