Is Direct Drive Really Better?

Sean, you forget that the high inertia set-up, as you put it, also has high torque. Torque being force X distance from center, the torque being exerted at the distance where the stylus is from the center. Having inerta as an added 'store' of force, is a good thing. The fact that the motor is low torque is irrelevant since the torque is multiplied by the 'pulley' ratios.
Put another way, depending on the polar moment of inertia of either system, the one with the largest moment of inertia will be less disturbed by quick changes of drag. The 'high torque' direct motor only delivers the amount of torque necessary to turn the platter at the constant speed under X drag conditions. Unless it can react immediately to the sudden increase in drag, it will be disturbed in speed. The high inertia platter however has torque stored, so-to-speak, as inertia and therefore is less affected by the sudden increase in drag.
I guess that that is your arguement?

Bob P.

Can't speak for Sean, but it seems to me that is the argument. For example, the Nottingham has such a low torque motor (but high inertia platter) that you have to give it push to get the platter going. That's by design.

Bob ... actually you and I are in agreement. The torque is either in the high mass platter, or in the motor, or it is in both. Where it is doesn't matter, what matters is that there is plenty of it.

I'd even go further and say that, I would expect the theory to favor a belt driven table of very high mass, and with a very low torque motor, since a revolving high mass not only has plenty of torque, but because of the low torque motor it should also have a very high degree of speed stability, and noise rejection. The difficulty in the high torque motor approach is guaranteeing that the high torque motor is low noise, and has an extremely stable rotational speed.

But I'd still like to hear a Lenco, Garrard and SP10, and I'd be happy to buy whatever sounded best to me, regardless of my theoretical preconceptions.

My experience has been that solo piano is the torture test for turntable speed stability, so a dose of Beethoven piano sonatas should be all that's required to find the best turntable.

Lloyd Walker tells an amusing story that some of you may have heard... he was demonstrating his Proscenium turntable at a show a few years back when some attendees came in to talk with him about why he didn't use a high torque direct drive design for his table.

Their argument was that only such a design could maintain the pitch stability and drive that music required and that any belt driven turntable (such as the Walker Audio design he was demonstrating) was fundamentally flawed in design.

Lloyd was playing a piano recording at the time (certainly a good test of pitch stability). So, rather than spend a lot of time arguing, he pulled out a pair of scissors and CUT THE DRIVE BELT.

The record continued to play with no discernable change in pitch for at least 20 seconds.

And thus ended the debate.

NB: I own a Walker, so I've got a bias. But I've done the belt cutting routine here just to test Lloyd's story. Amazing what a virtually frictionless high mass (80+ lbs) platter design can accomplish with an extremely low torque motor. (Agree with you on this Seandtaylor99.)
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Hmmm....lots of misunderstandings here. First, to 4yanx and high-end designers. I don't mean high-end turntable designers, but designers of other equipment for which they want the best source they can find in order to demonstrate their wares to best effect. Of course a high-end turntable manufacturer won't be interested unless they use titanium nitrate and high-pressure ceramics developed for NASA to justify high price-tags, as you say. But when the high-end designers, of amps, preamps, speakers and distributors of the same start to use Lencos, Garrards, or other large idler-drives, because they don't sell turntables and don't give a rat's ass what they use as a source, so long as it makes their products sound as good as they can get them to sound, then people will sit up and take notice. This, unfortunately, is the situation, and so I'm opening a new "front". My concern is strictly with the truth, or more accurately, empirical reality. By your own honorable admission - and caveats about getting it set up right notwithstanding (this applies to all components, n'est-ce pas?) - the rebuilt Lencos beat belt-drives at several times their price, and I wonder if you have, in fact, ever heard a belt-drive, at any price, which could even match or beat a properly restored and implemented Lenco in a fair comparison?

Then there is your message here - "The best of our efforts will compete with turntables costing many times more, and we have friends that can attest to this fact. In some ways, they sound better, especially in the lower end and in that indefinable “pleasure” factor. I am neither an engineer nor a psychologist so I will not try to explain the “boogie factor” these tables seem to have." The fact that you can hear this, and it is repeatable from Lenco to Lenco despite differences in plinth materials, design and weight, points to something in the Lenco proper which accounts for this: it is superior speed stability, which in its turn underlines lack of same in belt-drives. It is, being audible, an empirical fact, and being audible there is a physical reason for it, no need for psychology beyond the human ear's EXTREME sensitivity to pitch (speed stability). It has speed stability which is superior to that of the belt-drives you have heard or compared it to. The rest, high frequencies and such-like, can be tuned by implementation, materials, tonearm/cartridge. And, since this "indefinable pleasure factor" is in fact beautiful music-making, then I submit that, this being THE most critical factor in building a successful stereo system and the whole reason we are in this game (not to reproduce boring and unpleasurable music), the Lenco and the idler-wheel drives it represents are quite simply superior to belt-drives, period. It's not about trumpeting the success of this design and "you have the wrong one", it's about deciding which is the best system. How many audiophiles buy one turntable and stay there? Yes, they are currently happy with their given belt-drive, but they will, down the road, spend likely several thousand dollars on another belt-drive, which is inferior to an idler-wheel drive, especially at music-making. If a large company with the resources decides to get into the game and start to produce reasonably-priced idler-wheel drives, we will ALL benefit. In the meantime, we can either get into a restoration DIY project, or get it done, still for far less than the high-end belt-drives which are their "competition".

And while it is true that Garrards 301s/401s and Thorens TD-124s have always had a following, my own thread was never about Lencos, it was using the Lencos which could be had cheaply, as bait to get the world to participate in testing out my claim that idler-wheel drive was a significantly better system than belt-drive and had been unfairly assassinated by a concerted effort of the press and industry (reminds me of digital). I being I think the first, and if not then definitely the most vocal and activist, to step forward and make the unequivocal claim this is so (and for which I get roundly criticized in the current politically-correct "no system is better than another" Western climate, but the battle is what makes it worthwhile ;-)) and challenging the world to a showdown to prove or disprove it (check out my first colossal flop attempt, flop), after which I devised the crafty Home Despot tactic. This is my contribution to the evolution of audio, not simply the discovery of the Lenco (important but not that important by itself without the attendant examination of the logical implications). I discovered the Lenco, actually, because I could not find the Garrards 301/401 I was in fact looking for after tripping over a Garrard SP-25 at a flea-market in Helsinki (I had never even heard of an idler-wheel drive at that point, before the internet), tweaking it, and finding it significantly better than either my Maplenoll (still considered one of the Great Belt-Drives) or Audiomeca turntables in all the most important ways (amazing even at detail)!

Hi Sean: let me use another word, as by "torque" I was thinking, indeed, in automotive terms, in terms of "applied" force, in the sense of an active force, such as a motor. The torque, as in stored energy/moment of inertia, is not sufficient to combat stylus force drag, it takes an active motor force to push the platter through the dramatically-cut grooves and the variable stylus force drag they cause: it will still slow, the belt stretch, and then contract, albeit more slowly as it has to drag so much mass, and the motors used in belt-drives are insufficient to push the LP through and keep the speed rock-steady. In the case of an idler-wheel drive, the motor is powerful, spins at high rpms which by itself tends to smooth out speed imperfections, and it is securely coupled to the platter/flywheel by the rubber wheel, which does not slip, stretch or contract, and which in its turn regulates the motor, making its rotation more perfect. These three elements - powerful high-rpm motor, grippy wheel, flywheel-platter (especially in the Lenco) - create a closed system which utterly ignores stylus force drag, or the cartridge and arm action. The belt-drive/high-mass/high moment of inertia is not a closed system, the stylus force drag will affect the speed to a certain extent, and the proof of this is in the listening. I had a Maplenolll Ariadne with 40-pound lead/graphite platter (the prototype for the Walker Proscenium), and despite the 40-pound platter, it could not equal the Lenco for PRaT, dynamics or even detail and focus/clarity, and this was in the old days before the Lenco plinth and design underwent all sorts of evolutionary steps forward, resulting in a LARGE improvement in overall sound quality over the old early days. Since, I have not yet heard the belt-drive which can even come close to a giant Direct-Coupled Lenco (which maximizes the plinth's noise damping properties and provides for even more stable speed), and can one say that a VPI TNT does not even come close to a Clearaudio Master Reference? Even if this is so, then the Lenco does too and it will be an interesting comparison when finally I get the chance to do it, or someone else. Again, the proof is in the listening, keep your ears open for idler-drives at your local audio shows! I know they are currently fashionable at European audio shows.

Hi Jack, the Thorens is actually a quasi-idler-wheel drive, as the idler-wheel drives a flywheel, which is linked to the platter/main bearing by a belt, so it's back to square one. Given this fact, I expect the restored Lenco to sound quite a bit better. But, the Thorens has a heavier platter, and a high-speed high-torque motor, which belt-drives do not, so the results should be extremely pleasing nevertheless. I am actually currently working on a perfect TD-124 MKI which I will sell on after my experiments, and it has the iron platter. It does indeed attract MCs (MMs no effect) with their more powerful magnets, but the way around this is by use of a glass platter to raise the record at a great enough distance to eliminate this effect, which I have. Anyway, I will build it into a similar plinth to the one developed for the Lenco, high-mass and inert, and report on the experiment on the Home Despot thread (you can get immediately to the last page by clicking on the double arrows at the end of the page numbers). And btw, the Lenco properly implemented (not so difficult, but time-consuming) is in fact quieter than any high-end belt-drive against which it has been pitted so far, the latest local convert commenting that his Lenco is quieter than his Rega P9 with RB-1000 tonearm (which sonically is not even close to being in the same league, in any respect whatsoever), which currently gathers dust. In fact, two things leap out in any demonstration I have participated in so far, ahead of the bass and astonishing lively dynamics: they are all astonished at the extreme quietness/blackness, and they can actually hear the incredible speed stability, not as a result of clarity or detail or what-not, but as actual clearly audible and striking speed stability! Now THAT's speed stability.

I think I made this point once before. If the reason the Lencos sound better is superior speed stability, then CD should have kicked vinyl's butt long ago. I would look elsewhere for the reason you prefer the sound of idler wheels.

Interesting comment, Drubin. However, it could be that CD does kick butt in the area of speed stability but loses out on other aspects of continuity due to "bits is bits" fragmentation. You can't grind steak into hamburger and then make steak again no matter how constant the speed of the grinder or the ungrinder.

Agree with the viewpoint that, in principle (all other things being equal, which they probably won't be in reality), there should be no difference between torque stored as inertia in a high mass platter, and torque as applied by the motor -- at least in the moment of initial transient attack. But the dynamics of how the platter recovers lost speed in preparation for the next transient event, or during sustained peaks, may well be different, and maybe could favor the lower-mass/higher-torque model. (And/or also the model of active speed sense-and-control?) Anyway, there are clear advantages of price and ease of placement in not having to get a TT with a platter that's half your body weight. A lighter platter also eases the job requirement of the main bearing. A degree of flywheel effect is certainly desirable in any TT design, but to me there's something dissatisfying about the idea of always resorting to supermassive platters.

I'm not sure I can entirely agree with Johnnantais on a few other things, but he probably knows more about it than me. Still, I can't reconcile the blanket assertion that a motor turning at 1,500 RPM is intrinsically better than a motor turning at 33 1/3 RPM -- that high rpm "by itself" tends to "smooth out" speed imperfections. If we assume the same level (amplitude) of vibrational contamination for the sake of argument, the only difference, it seems to me, will be in the frequency and its harmonics, which will also alter the spectrum of intermodulation products. That will change the sound, but I don't know which one is better, or what might constitute the "ideal" RPM or frequency to superimpose upon the music signal (none would be nice). But I doubt it's as simple as saying "higher is better", especially when only one fundamental falls within the audioband (1,500 RPM = 25Hz, while 33 1/3 RPM is only about 1/2Hz). I'm not exactly sure if all this stuff is pertinent to the topic at hand though, maybe an engineer or physicist could elaborate further.

If we stipulate (correctly, I hope) that high torque is what pushes the platter through dynamic passages, then as far as I know, in electric motors lower RPM = higher torque (larger motor diameter does too, which DD's also generally have). I have zero experience with the big idler-drivers mentioned, so I'm guessing that for their motors to be both high-speed and high-torque, they must also be relatively large and powerful (higher amp). If so, wouldn't that increase the amplitude of vibrations vs. a lower-speed, lower-amp motor with equivalent torque? Obviously there will be a lot of other variables regarding how any two motors in question are made, but I wonder in principle.

However, it is undeniably true that the faster you spin anything that's not in perfect balance, the more violence will be imparted by its shaking. Can a motor be perfectly balanced? If so, I guess we wouldn't need to have this discussion. So, adding it up, I can't buy the notion that higher motor RPM's are somehow "better" for TT performance. I've always assumed one of the strengths of DD was the low-RPM motor: high-torque, low amplitude of vibration, low frequency of vibration. Somebody please point out the error of my thinking if I'm wrong. Absent the RPM argument, I haven't yet detected the theoretical case for why idler-wheel drive should be intrinsically superior to direct-drive. That it may prove subjectively superior among certain 'tables auditioned by certain listeners is another question.

Maybe I'm way off base somewhere here, but speed performance is measureable -- you don't have to depend solely on subjective listening impressions to find out about this particular factor. Does anyone know that idler-drive tables can have better wow & flutter numbers under dynamic playing conditions than a good quartz/PLL controlled DD? Are there any constraints that prevent a DD motor from being made just as powerful as for an idler-drive, if that's what one wanted? (Magnetic interference with the cartridge, perhaps? The platter's shielding ability may be limited, but I don't know -- I thought the Rockport DD was supposed to be terrifically powerful and nearly impossible to deviate the speed of. If you pay enough, you can get a high-torque/high-mass DD table, with the electronic control to harness both.)

To me, DD does seem to have several intrinsic theoretical advantages. One is that the motive force is applied without physical contact of the platter. If you use a belt or a wheel to transmit force to the platter, it must result in some added degree of motional friction, which must produce a characteristic resonance, much like road noise in tires (okay, so it's probably more like urethane skate wheels on polished marble tile, but the principle still applies -- it's still not silent).

Another is the fact that there's only one bearing, the ubiquitous main bearing. In any design with a separately housed motor, that motor must have its own bearings in addition to the necessary main platter bearing. Then there's shafts and pulleys or wheels -- they won't be perfectly concentric. DD does away with powered driveshafts, pulleys, and/or wheels.

I tend to think simpler is better (simpler, but not too simple! ;^) A TT doesn't get any simpler, mechanically speaking, than a DD: the plinth is the stator, and the platter is the rotor. In any other arrangement, the separate motor can and will move in relation to the platter, which causes variation in platter speed. In a DD the motor can't move relative to the platter, since the platter is itself one half of the motor.

Another thing: I don't know if this absolutely has to be the case, but as far as I know only DD's incorporate electronic sensing and control of platter speed directly, rather than control of motor speed (but typically without sensing, I believe) with a somewhat flexible linkage in between it and the platter. I know which arrangement seems like it would be better to me, but I'm open to arguments. Again, though, the results can be measured.

Along those same lines, there's the issue of how correct speed is established in the first place. With a PLL sensing system in place, it's easy to add calibration to a quartz crystal reference, a very much higher and more constant frequency than (and totally independent of variations in) the AC powerline. Who wouldn't want that if you can have it? And again, the results are measurable.

I've often seen an argument against PLL-controlled DD's that usually goes like this: They are constantly "hunting and pecking" for the correct speed, but never settle on it. I have never understood this. Any electric motor operates in what is termed a "kick and coast" fashion, dependent on the number of poles. More poles would seem to be obviously better than fewer poles, but I don't know that the number of poles possible is in any way linked to or limited by drive method. Anyway, it seems to me it's primarily this kick and coast phenomenon, dynamic stylus drag aside, that's primarily responsible for any TT not constantly rotating at exactly the correct speed, no matter how it's driven. Why this is blamed on implementing a PLL is something I want to know.

Another thing I want to know is why DD is often portrayed as constituting a "rigid coupling" between the motor and the platter (never mind that this doesn't make any semantic sense, since in a DD the platter is in fact part of the motor). At times I almost get the feeling that some audiophiles who haven't owned a DD visualize it as simply consisting of a belt-drive type motor -- meaning a self-contained unit with a housing and a protruding driveshaft -- with the platter stuck on the end of the shaft instead of having a pulley and belt in between. (If that describes anybody reading this, go to the website Viridian linked above and look at the platter-off pics of the SP-10.) Anyway, "rigid coupling" seems to imply that the platter can't "slip", which of course is 180 degrees opposite of the truth -- any DJ knows that only in a DD can the platter be freely spun manually when not under power, or manually deviated with precision from constant speed when under power, from which it will rebound when released. ("Rigid coupling" also implies vibrational transfer, which again to me is a conception misappropriated from the paradigm of separately-housed, self-contained motors physically linked to platters and plinths by compliant couplings.)

As I understand it, in typical audiophile belt-drivers, the elasticity of the belt, combined with the inertia of the massive platter, is supposed to mitigate the kick'n'coast speed variation from the motor. Of course this can't simply be "gotten rid of" -- the elasticity and inertia combine to spread its effects out in time, reducing the amplitude peaks, effectively averaging the variation in speed. Well, platters in DD's also have mass. The "slippage" and subsequent rebound that I described when a drag or an energy input is applied, isn't that functionally equivalent to belt elasticity? It seems to me that in a correctly designed DD, the PLL sense-and-control system, combined with the platter inertia and the natural ability of the platter to smoothly and infinitely vary from constant speed and then rebound without introducing mechanical friction, can constitute exactly the same kind of "averaging" mechanism that smoothes the kick and coast impulses in a belt-driver. The difference is you don't need a supermassive platter or the attendent pitfalls of a belt/pulley/separate-motor system to do it when you've got active speed control working for you.

I know many audiophiles regard the notion of any "servo" or "feedback" type of operation as something they're allergic to, whether it's negative feedback in amplifiers or servo control of subwoofers. As the saying goes, you can't correct something that's already happened. Same for many active vs. passive questions (though not always). I also know many engineers would argue with this attitude and say it's not that simple or universal a truth, that there can be well-implemented applications for feedback-type mechanisms that don't harm sonics in unintended ways.

I can't comment on all that stuff, or its applicability to DD TT design, with any authority (though I don't recall anybody saying that adding an outboard speed controller to their belt-drive TT made it sound worse). Yeah, I own a DD [KAB-modded SL-1200], but like I've said before, I lack the comparitive expeience to make pronouncements about relative superiority. But I also note, with no real satisfaction, that probably no audiophile, no matter how experienced, has ever had the opportunity to compare two turntables whose only difference was method of drive. As we all know, there's a host of other factors which affect TT sonics besides drive type. I also acknowledge that measurements, such as I touted above, often don't tell the whole story sonically speaking (which simply means we need other, better measurements to correlate with what we hear).

More important though are, as I see it, two questions: The one Drubin asks, i.e., do any of the DD's available in the moderate price range (current or restored) warrant consideration over the entry-level and next-tier belt-drive audiophile standbys (none of which are terribly massive due to their reasonable cost)? And the one Macrojack wants to know: Is it time for high end TT makers and audiophiles alike to reconsider the relative merits of the DD option -- could it be exploited to make even better tables than are generally available right now (and if so, at an attainable cost)? I admit I don't know the answer to the first, but feel the second has got to be a yes if at all possible.

If this DD revival stays I'll be selling my modded 1200. Why? Because Matsushita will start making the Technics SP-10 MK IV !!! Oh man, a 10-12 lb copper and aluminum platter w/ 24 pole linear quartz lock DD brain--and a home made Caribbean Moca wood base. YES!!!

DIRECT DRIVE OR DIE.

John

"The torque, as in stored energy/moment of inertia, is not sufficient to combat stylus force drag, it takes an active motor force to push the platter through the dramatically-cut grooves and the variable stylus force drag they cause: it will still slow, the belt stretch, and then contract, albeit more slowly as it has to drag so much mass, and the motors used in belt-drives are insufficient to push the LP through and keep the speed rock-steady. "

Now re-read Rushton's post. If stylus drag is really capable of slowing an 80lb platter how could the walker continue to play with the belt cut for tens of seconds ?

Can people not see the equivalence of torque by stored inertia and torque by electrical energy (motor) ?

Again, I'm perfectly open minded when it comes to purchasing, but those who decry belt drive must first give some reasoned argument as to how a low torque, massive platter design is supposed to be slowed by a minute diamond dragging through a groove with a tracking weight of only a few gramms.

Hey Sean.

"Can people not see the equivalence of torque by stored inertia and torque by electrical energy (motor) ?"

No they cannot as they do not want to. If you look at the actors on this thread you will see they reappear numerous times on other threads bashing belt drive TT. I have posted questions like yours in the past and never got a coherent or sensible response.

A poster in this thread managed to name 4 DD TT which were reputedly good (note reputedly) and then went on to say that since a SL1200 is such a good seller that "these things point toward a degree of superiority". When I read that I gracefully declined to continue further conversation.

This simply yet another example of folks confusing consensus of opinion with facts. Sadly this is quite prevalent amongst audio folks.

As a hobbyist/DIY-er myself, I fully understand (and have empathy for) their passion for their idler wheel and/or DD turntables, so I will take no pleasure in bursting their little bubbles.

Regards
Paul

The universality of torque aside, Walker's cut-belt demonstration was a bit of circus stunt. Of course the pitch and tempo of the record dropped during the 20 seconds -- that's a fact of nature -- it just did so slowly and not very much, so nobody noticed through their surprise. If they didn't notice that, then they didn't notice whatever effects of dynamic stylus drag were superimposed on that -- not only because of shock and awe, but because there was no reason for those effects to have changed much before and after the cutting of the belt. The massively heavy platter minimized those effects before the belt was cut, not the motor, and removing power didn't change that. Whatever dynamic speed modulation by the stylus sounds like, it couldn't be a gross effect, it probably manifests as a subtle alteration of textures or something, maybe a bit of clouding of the soundstage, who knows. Hell, there are ways in which you could predict *any* turntable would sound *better* without its motor interfering, if only they all could keep spinning away like the Walker. (Maybe cutting the damn belt even granted it some of the virtues of direct-drive for a time ;^) Point is, there was never any question that an 80lb. platter on an air bearing for $20K+ could help overcome dynamic stylus drag, the real question is if that's the only way, or even the best way. (I've always assumed the really massive platter jobs must have very low flutter but rather high albeit long-period wow, and maybe that's a smart tradeoff.) Or if any of that matters to the sound nearly as much as the resonant characteristics of the turntable -- if not, then use any drive method, just make sure the thing has good vibrations.

This is truly a case of getting the cart before the horse ...and arguing that it belongs there.
The real issue is what performs better in actuality and not what should sound better. If we find that we are getting better results from one approach, then theorizing about why is appropriate but speculation about which SHOULD be better is pretty useless.
The question that started this discussion asked which IS better, not which should be.

"You can't grind steak into hamburger and then make steak again no matter how constant the speed of the grinder or the ungrinder."

Actually (in theory) you can. A sampled waveform, sampled at a frequency of at least twice that of the highest frequency in the waveform, that is reconstructed with a sin(x)/x filter will perfectly reconstruct its original signal. Once again theory says that digital can produce perfect sound. The problems are in the implementation.

I know much less about the science and engineering of this subject than most of the excellent posters in this thread, but I feel the point I made above merits further exploration. Tom (Macrojack), your response, which is essentially that problems with the CD format obscure the big payoff it delivers in speed stability, is certainly credible, but I'm not willing to let it go at that.

What are the sonic benefits people ascribe to DD and IW? Better PRaT? What else? If this were due to better speed stability alone, surely we would hear at least some of this benefit from CDs. Do we? As piano is the reference standard for hearing pitch stability, shouldn't this be obvious from CD? (Some people think it is, but not all of us.)

My layman's hypothesis is that average speed variation from the reference (33 1/3) is more significant to sonics (and more widespread) than the very tiny moment-to-moment stability issues that are being argued about in this discussion. Rega tables run fast and -- guess what? -- they have great PRaT.

And let me toss out another idea. How stable, moment-to-moment, was the cutting lathe? And how close to perfect 33 1/3 was it? These issues confer obvious and huge advantages to digtial recording and playback, certainly on paper (listen up, Miss Pickler), but in actual practice they do not seem to be as significant as one would have thought. Ditto with inner groove distortion, the crude way in which stereo is extracted from vinyl (see an earlier thread about mono cartridges), and numerous other shortcomings of the vinyl medium.

Goodness me, I never realized that intra-analog vitriol was just as rampant as the digital-analog variety! But I for one don't find the arguments particularly strong on either side. And I don't think it's even possible to do a fair listening comparison of these two drive technologies, because I doubt you could hold everything else in the system constant.

Isn't the DD-vs-belt debate really a question of which technology offers the better trade-off between speed accuracy and rumble? And while not everything can be measured, isn't it true that those two things can be? So let's see some numbers--preferably independently verified. Where's the belt-drive table that is the equal of any DD in speed accuracy, and bests DD on rumble? Where's the DD unit that can say the same in reverse? Granted, this wouldn't settle the debate--measurements never do--but it would at least give us something solid to sink our teeth into.

Screw the numbers. Trust yer ears. I don't see why at least a very close approximation of a controlled setting which would allow a one-to-one-to-one comparison of table/arm/cart combos could not be accomplished. At least enough so that one could make a case for THEIR listening preference (what counts most). Many have done so informally and anecdotally. And, to the extent they are satisfied with their choices ends the argument in their minds. Personally I’d rather sink my teeth into the music I hear than the numbers I see on a sheet of paper, but I understand you desire to have something more seemingly solid.

Tom, my arguments address the conversation that deals with why one technology is better than the other, which has been the dominant conversation in this thread. That's not the question you asked, but it's where the discussion has gone.

I don't count myself among the audiophiles who do not care to ask why but just accept what they hear as true. It's a fine line, of course, but to abandon reason and critical thinking is unacceptable to me. If belt drive superiority proves to have been a distortion that the market adopted wholesale 25 years ago, it is partly because we accepted the erroneous arguments for why it was superior. Same will be true here if we buy into statements such as "pushes the platter instead of pulls it" without critically examining their merits.

Paul: I agree that the remarkable longevity and popularity of the SL-1200 says exactly nothing about either the worth of that machine to audiophiles, or the worth of DD in general to audiophiles. Now, that fact may say more about audiophiles than about DD (or the SL-1200), but the argument's a false sylogism nonetheless. Granted, perhaps not a lot of products without some sort of fundamental merit do as well over decades as the 1200, but a few do -- witness the Bose 901. But the 1200's endurance springs mostly from people who must depend on it in a professional context, so that the machine has its virtues is uncontested; the question is whether one of those virtues is actually sound quality. I have my inexpert opinion on that, but no "bubble" to burst, trust me, and I do not "bash" BD. If you count my response among those you classify as not being sensible or coherent, then that's your privilege.

So what we mostly have are reports from guys who've owned both. It seems noteworthy to me that among the A-goners who've given good DD a chance and also have experience with good BD, I don't think there are any who dismiss DD out of hand, and a few who specifically extoll the potential of the 1200. (If you want to take Psychicanimal off the table from the start, be my guest; we all know where [and how] Francisco stands, and still life goes on.) In the final analysis, online anecdotes mean less to me than what I hear in my living room, and that I find almost entirely satisfactory and beautiful, especially since the KAB mods. Which shouldn't necessarily say anything to you. Anyway, regardless of the motor/drive system, the 1200 still can't sound better than the basic competence of its plinth, platter, bearing, and tonearm, which *ought* to mean it can't bat in the same league as the big boys (but not because any of those things, save perhaps the platter, is notably deficient IMO). But please feel free to take a stab at any of the theoretical points in favor of DD I raised above.

Macrojack: Your last post, it seems to me, actually bears little relation to the question you appeared to ask at the top (reread it), or the debate you seem to have been encouraging since. I think a discussion of theoretical potential and pitfalls is totally appropriate, and in many ways a good chew over theory is the best thing you can read on a forum like this. It can teach you new ways of thinking about what you hear. If you expect to settle anything by people recounting their personal experiences and opinions, you're probably going to be disappointed. Online forums are about discussion of audio and batting around of ideas in addition to experience and opinions, and the whole activity is an entirely different animal from actually listening to music or gear. In any case, there are too many people here lacking both the carts and the horses to put one before the other... ;^)

Hi Zaikesman.

No my comments had nothing to do with your posts. I had a look at http://de.geocities.com/bc1a69/index_eng.html after reading one of your posts.

My post is indicative of the frustration I have with folks who believe that a consensus (or should I say chorus) of opinions constitute a fact.

I have spent some time with an idler wheel (Thorens TD124) and the sound was really not up to scratch. Compared to a TD125 I had at the same time it was downright bad.

However, the after reading up on DD tables I think there may be something to them. The points laid out in the web pages and your posts do sound plausible. Personally my only preference is for sound I enjoy, not BD over DD. I need a project for summer so I want to see if I can lay my hands on something like a Denon DP6000 and see what they are about.

My only concern is that due to the fact that these tables have not been in production for a while, repairs may be an issue if the need arises.

Regards
Paul

I don't see why at least a very close approximation of a controlled setting which would allow a one-to-one-to-one comparison of table/arm/cart combos could not be accomplished.

Of course THAT could be accomplished. But that tells you absolutely nothing about whether belt or DD is superior. It only tells you whether one combination sounds better than another. If that's all you want to know (and for most audiophiles most of the time, it probably is) that's fine. Just don't draw unwarranted conclusions from any such comparison.

Thanks, Zaikesman, I was wondering about that taste until you pointed to my foot in my mouth. I did, rather pointedly, ask for opinions.
I've read some very good arguments on all three sides and it seems that not much has been determined about superiority or inferiority. As someone said, the head to head comparison is not something that can be done with any precision, measurements are just measurements and all sonic evaluations are subjective, so it seems to come down to one of those Joe Louis vs. Mohammed Ali debates where everything is based on projection and extrapolation.

I was fishing for a consensus of some kind and it appears that presently there isn't any but as I said earlier I sense a developing inclination back toward DD and maybe 4yanx is correct to call it "buzz". Nonetheless, it may be that the fracture in our ranks has something to do with "buzz" vulnerability. It may just be that mine is pretty high.
I've been using a Well Tempered Reference table for 12 years but in the past month or so I have acquired an SP-10, an SL 1100a, an SL 150 MK II,and a Luxman PD 441 for evaluation. The WTT is for sale now and I'm looking forward to evaluating the buzz. A friend has predicted that I will find the Luxman to be the best of what I have. Has anyone else used one?

Pabelson, if you think that the whole thing boils down to speed accuracy and rumble, you are sadly mistaken. Internal resonance within the drive system and resistance to external vibration and the period and frequency of those vibrations are just three more of the various factors that come into play.

I'm not talking about "the whole thing"; I'm talking only about factors for which one drive system or the other has an obvious theoretical advantage. So if you want to convince me that I'm mistaken (and I might be--I certainly can't claim any real technical expertise here), then the first thing you have to do is offer a plausible reason why one drive system would be presumptively better than the other for each of the three factors you mentioned.

Even if the factors you mention are relevant to the belt/DD question, I suspect the speed accuracy/rumble tradeoff is still the dominant factor. If one drive system could be shown to be superior in minimizing both speed inaccuracy and rumble, I supect this debate would be over. I seriously doubt the factors you mentioned could tip the scales in the other direction.

Of course THAT could be accomplished. But that tells you absolutely nothing about whether belt or DD is superior. It only tells you whether one combination sounds better than another. If that's all you want to know (and for most audiophiles most of the time, it probably is) that's fine. Just don't draw unwarranted conclusions from any such comparison.

So what would you rather have, something that sounds best to you or something that the numbers say is "superior" to something else? The definition of "superior", at least im my music room, is what sounds best, not what some imperical set of measurements say. A bucng of the 70's amps were so good by the numbers that they should have been creating live music - unfortuantely, many of those same amps sounded like crap. I would draw a conclusion that something was better based on the sound it made everytime and look at a decision based on measurements as the unwarranted choice. But, that's just me, maybe.

Drubin, I don't think accepting what one hears as true mean abdicating reason and critical thinking. Just saying that measurements can lie. When they do, THAT is whan you NEED reason to tell you the REAL truth! ;)

I'm in violent agreement with you about measurements, David. However, when what I hear flies in the face of reason (irregardless of measurements), I want to know why, or at least I want to think it through. That's just me, and it reflects my self-doubting personality.

I'll make a confession that may get me kicked out of the club. I used to believe fiercely in "trust your ears," but I have come to suspect that our ears (mine at least) can sometimes lie to us also. This does not mean that I choose what measures best (I don't pay attention to that), only that I pause and reflect if something doesn't make sense. I may end up choosing components or techniques that don't make sense but sound best to me (e.g., using a linestage). The thing is, I don't do so without first questioning it, and I continue to question it even afterwards.

Drubin,
I have a friend who insists that perception is reality. There's something about the comment that disturbs me but there's nothing there for me to contradict. That said, I certainly wouldn't think to kick you out of the club. In fact, your candor is grounds for promotion. I would guess from your writings that you would be more comfortable with 4yanx in the hearing dept. than with seandtaylor in statistics.
Personally I wouldn't consider a thread successful until it attracted your comments.

4ynx: Do you not understand the difference between "this table/arm/cartridge sounds better to me" and "since this table/arm/cartridge sounds better to me, it's drive system must be better"?

Macrojack, you are one fine gentleman.

Dan, I wrote this dreadfully huge post disagreeing with your presumption that static inaccuracy in baseline speed is more of a factor than dynamic micro-speed variations. I don't want to post it the way it is, so I'm just saying so, and we'll see if I ever elaborate ;^)

Then send it to me in email. I'm very curious to hear what you have to say on the subject.

I use a SUPERIOR belt drive mechanism. under the platter a large 10lb. live rat (rodent) runs on a BELT, the heavy 50lb platter (and three ball govenor) does indeed smooth out any speed irreglarties. There is NO measurable rumble. Completely independant of powerline noise. Feeding and clean-up are manditory.

Mint604,
You bring up an interesting point. All (4 now) drive systems require some kind of maintenance and I suppose it should be a condideration in these comparisons. All the other motors need lubrication and yours requires nutrition. The IW has the most moving parts and would presumably be the highest maintenance system. BD probably only ever needs a new belt although I guess bearings and springs could also wear. With DD the only issue beyond lubrication would be the potential for motor failure and that would be fatal I imagine to a vintage table. Does your rat work quietly?

Dear Macrojack: I think that because there are several subjects on it it is almost imposible to tell which one is better: DD or BD.

If we take two of the TT primary functions: speed accuracy and speed stability, we can conclude that the DD beats the BD system: example, the Walker one has 0.002% on this spec against 0.001% on an SP 10 or Exclusive.
If we take the wow and flutter, the Sp 10 beats ( easily ) my Micro Seiki RX 5000: 0.015% against 0.025%.
We can take too the Rumble and here in the case of Walker or Avid it is around 90 db against 92 db on the SP 10 or 95 db of the Exlusive one

Btw, I own SP 10s, Denons, Micro Seiki, Luxman and Acoustic Signature.

From the point of view of how it performs on their designs the DD ones beats the BD: you can " see " at the measurements and this is a fact, period.
It is curious the BD manufacturers almost don't give almost any specs about: I wonder why?.
All those specs are extremely important to know about the quality build design if not which were or which ones are the TT targets on the TT design and how the designer compare the result ( build ) against those targets ?. Of course that the TT designer can had other kind of targets but it does not sense to me if he do not take in count those ones like speed accuracy and speed stability between others.

The TT specs can't tell me " per se " how good is the music reproduction performance but tell me how good care take the designer on the build of that unit and at least on the speed spec can tell me what " to wait " for.

Now, the " best voted " today TT is the Rockport that is a DD design and in the other side the Walker is the best example of what we can have in the BD designs.
Both designs go to an extreme design, here we can't say ( real ) which is better because in both trhey take in count almost all the issues for a perfect TT performance design: speed accuracy/stability, kind of motor, platter resonance/vibrations, energy disipation, plataform, air bearing, tonearm, quality on execution, " beauty on that execution ", etc, etc.

Which one do you like and which one performs better? ? , this is a subjective answer and we can have different answers about like different persons we are.

Which one is better?, here we have to go for facts: measurements, something objective and for this point of view the DD is a better one.

I send to build my plynths of my SP 10 and Denon TTs with a solid beautiful marble and Onyx one piece stones ( 40 kg ), as a fact this plynths function like the tonearm boards. I use the Audio Technica pneumatic suspension footers and tip toes like between TT and the plynths.

These DD TTs are very precise and have better music sound reproduction quality performance at both frequency extremes than my BD TTs: this is very easy to find out, play a piano work in either design. Why am I not using them?: because I need to mount, at least, three tonearms in each TT ( that I can change in any moment ) and the Micro and AS ones comes ready to work on it.
One of my future targets is to build a system plynth/arm board for I can use my DD TTs in the same way that my BD TTs, in the mid time I have to accept a 95-98% ? quality performance of what I can achieve with my DD TTs, not big deal.

Regards and enjoy the music.
Raul.

Raul: Wouldn't the rumble specs, at least, be somewhat dependent on the plinth made for a deck-mount DD?

Anyway, whatever one thinks of Michael Fremer, to me it's interesting that a guy who's critically auditioned that many turntables, and proclaimed the direct-drive Rockport Sirius to be the uncontested best at the time he had it, later decided the belt-drive SME 30 (at about 1/3 the price without arm) equalled or slightly bettered it (with a Graham arm fitted). This is notable not only from the DD vs. BD perspective, but because the Rockport had an integral linear-tracking arm (Fremer has in the past has extolled not only the theoretical but the actual benefits of linear arms if properly executed), air bearings all around, an integral active isolation stand, the more complex motor controller, and was maybe 4-5 times as massive -- none of the which the well-executed but by comparison conceptually basic SME could match on paper. The Rockport may indeed have the better specs -- I don't know that we know, but anyway at a certain point a few more -dB or a slightly lower % may not matter in practical terms -- but for all its engineering heroism, if it doesn't sound clearly superior at its much higher price, which TT is ultimately the better design? And why would a designer then need to go to the trouble and expense of making a direct-drive system in this day and age?

To me the real-world value of DD might be where it is right now on my gear rack: a relatively inexpensive, highly durable, low-maintainance, operationally flexible, speed-accurate, good-sounding TT for not a lot of money, that probably has significantly better specs than any belt-driver in its price range. Which drive method is allegedly "superior" at the top end of the food chain is a debate for others, and hypothetically interesting as the question may be, the evidence could point toward factors other than drive method ruling the roost at that level.

Zaikesman,
I feel myself being pulled in your direction. I replaced nearly $10K (used value) worth of separates with a $700 integrated amp that actually sounded better. Boy did that ever feel good. I'm currently looking to see if I can accomplish something like that with my analog. That's how this thread started actually. I did something similar with speakers and cables.
Tom

Direct drive or die.

Raul! What? Out of all those arms, cartridges and table you don't have a good idler wheel? I think you're a great candidate for a Lenco!

Dear Zaikesman: +++++ " To me the real-world value of DD might be where it is right now ..." +++++

I agree, we can buy a SP10 MK2 for 400.00 dls ( with out plynth and tonearm ), a Denon DP 800 for 500.00 0r a SP 10 MK3 for 1,200.00. Btw, all these TT designs comes from more than 20 years ago!!!! ). Any one of these TTs ( with the right plynth/footers/tonearm/mat) can compete not with ++++" any belt-driver in its price range. " ++++ ( like you say ) but with the 40K+ Walker BD TT and for a ridiculous price fraction.

+++++ " Which drive method is allegedly "superior" .." +++++

IN my opinion and if we take only the drive system " per se " then the DD is a superior drive system over the BD one. The first and most important function on a TT is the speed accuracy/stability and here the BD system can't compete with the DD system and this is a fact that any one can see it through measurements and own TT specs, period. Btw, ( at least on my TTs ) one musical reproduction characteristic on the DD TT is the more real and natural decay time of the notes, this give to the sound reproduction a better feel of the " live music " against the BD TT.

+++ " .. the evidence could point toward factors other than drive method ruling the roost at that level. " ++++

Yes, there are several other factors than drive system where one or the other could be superior.

About Stereophile: well the champion at the moment is the BD design Continuum for around 90K, speed accuracy? : 0.006%.

Regards and enjoy the music.
Raul.

Raul: I wouldn't know about the sound quality of relatively inexpensive DD's competing beyond their price range (though you might), I was only stating about their speed accuracy and precision. But a caveat has to be acknowledged: published speed distortion specs only deal with combined gross levels, leaving us in the dark about spectral and temporal character. The possibility exists for one TT to have lower measured speed distortion than another, but of a sonically nastier nature.

It would be very hard to find an SP-10MKIII for 1200.00 in any decent condition. The last one I saw on eBay went for well over 4000.00.

So...now I have to look into DD or Idle-wheel drive TT?

Here I am ready to upgrade my TT and arm with a VPI, Galibier or Teres and a Schroder or Tri-Planer. Now we have the Garrard 301 Idle-wheel......and Lenco.....OH MY!!!! Now you have force me to read the entire "Home Depot" thread :(!!!

Rick (RWD)

For people like Raoul, don't forget EMT idler drives.

Macrojack, I question your conclusion. I think a better read is that both belt and direct drive can work wonderfully, but it really depends on the implementation. One is not really better, each simply has a different set of compromises.

Why is that the wisest answer to so many questions, be it CD/speaklers, cables, tube V SS above all. It is all in the implentation. There are many more belt tables, but some excellent DD ones. being from the UK and a few miles from Loricraft, Garrard springs to mind. It is hard to beat a well renovated and plinthed 301/401 and a 501 would be my ideal, if I could afford it. They seem particularly hard to beat for base response.
A different and more interesting question would be, if you were going to make an ultimate, cost no objest turntable, would it be belt or direct drive? They all really are belt drive, but is that because the extra tooling costs of DD, make it prohibitive when you are going to be selling 10's or 100's, but not 1000's of units. I think that is the reason and it would be possible to match the ultimate belt drive decks, but who knows as there are'nt any to audition.

If I may be permitted to point out something that seems to have been missed here, there is more to a turntable than speed stability, although speed stability is a very important requirement.

Another factor which comes into play is the effect of vibrations or other potential movements in the main bearing assembly(and thus the platter).

If stylus drag can affect the speed stability of a heavy platter or even a motor's torque, then it can also generate lateral movements of similar proportions, due to the angular nature of it's movements as it traces the groove. Externally generated vibrations can affect this also. Since any lateral movement allowed by the bearing/platter can materially affect the amplitude of the groove modulation being traced at the time of that movement, it can cause information loss or modification, based on that unwanted movement of the platter relative to the stylus. But wait, you say, the arm could be moved more easily because it has less mass, and I say that if the arm deflects, then you get similar information distortion as well.

Now, how does this affect our discussion?
Quite simply because direct drive motors generally(and I use that word advisedly) use their drive shaft as the main bearing, which typically does not have the precision tolerances of a belt-drive system's main bearing in a good turntable. In addition, making the platter part of a motor which has inherent vibrations as a natural characteristic is not conducive to ideal conditions for the stylus/groove relationship.
So, even if a direct drive does exhibit a slightly better measured speed stability, there are other factors involved besides that.

Also, wow and flutter are very different speed variations, and to lump them together as "wow and flutter" is deceiving at best. Wow is much less easily perceived by the ear than flutter, and 2 tables with the same "wow and flutter" specification can sound quite different, especially if one has mostly flutter, and the other has mostly wow component in that spec.

To sum up, all methods of analog drive systems have their pros and cons, and none is perfect, and implementation may be more important than basic concept.

To focus in on speed stability alone, with no discussion of other meaningful design aspects is incomplete and useless. I've heard very good sounding turntables of varying drive system designs, and also some terrible ones too.

Tunnel vision is not the most productive way to analyze componentry.

David12, if I read your post correctly, you seem to be saying that the Garrards are direct-drive (DD) turntables. They're idler drives.

TWL -- Glad you could make it. Upon looking at the design of my Technics DD, I see that there is no main bearing per se but rather a broad based rotor/stator interface. The notion of that being rocked or deviated from its center seems remote given its diameter, mass and magnetic hold. After all it isn't a pencil point on a hard disk balancing a 12 inch diameter spinning disk. With the Technics table the motor is about 4 inches in diameter and in the case of the SP-10 it is screwed to the motor assembly. Very stable.
I also wonder to what extent the gyroscope effect might assist in stability in both designs. Does the platter spin too slowly for that to be meaningful. I have observed that a spinning top is rather stable at high speeds but loses that stability as its rotation slows. Does diameter of the top add to its stability to overcome slowing? Is 33 1/3 fast enough to have this influence?
Time for Seandtaylor and the physicists to come back to the discussion. I'm just tossing out questions that I can't answer.

Hold up, I think both both TWL and Macrojack have a couple things wrong here (not that I don't agree with most of the gist of what Tom has said -- I think I said some of the same stuff myself above :-)

"...direct drive motors generally (and I use that word advisedly) use their drive shaft as the main bearing, which typically does not have the precision tolerances of a belt-drive system's main bearing..."

I believe this is a common misconception, which I talked about in my first post to this thread. I may not always know about "generally", but specifically, a DD like my SL-1200 >>does not have a drive shaft<<. The main bearing is similar to the main bearing in any conventional BD, passive meaning unpowered. The motive force to rotate the platter is applied purely by touchless electro-magnetic impulse -- no shafts, wheels or of course belts involved. (Please also see my first post.)

"...Upon looking at the design of my Technics DD, I see that there is no main bearing per se but rather a broad based rotor/stator interface. The notion of that being rocked or deviated from its center seems remote given its diameter, mass and magnetic hold. After all it isn't a pencil point on a hard disk balancing a 12 inch diameter spinning disk. With the Technics table the motor is about 4 inches in diameter and in the case of the SP-10 it is screwed to the motor assembly..."

I think maybe you're being fooled by the appearance of the TT with the platter off. If the SP-10 is anything like an SL-1200, the platter fits over the conically-tapered brass sleeve which forms the base of the spindle, which is integral to the main bearing. When you remove the platter, the spindle is therefore left behind -- you can rotate it by hand. That is the main bearing. What you're describing as 4" in diameter is the stator assembly, which is not "screwed to the motor assembly" as you put it (not sure if you meant to write it that way, since it does't make much semantic sense), but bolted to the cast aluminum chassis, the bearing housing of which you can see centrally located within the stator ring at the base of the spindle/bearing. (Again, if it's anything like the SL-1200 -- please let me know if I am wrong in anyway in translating this arrangement to the SL-10.)

I would recommend anyone fuzzy about the details who really wants to get a feel for how this works to take a trip down to your local pro-sound shop that sells DJ gear and ask to see their display SL-1200 with its platter removed. (With the power turned off, place thumbs or fingers in the opposing holes provided for this purpose, alternate gently lifting one side and then the other to unseat and then carefully lift straight up). Everything I'm talking about should become very clear.

Zaikesman,
My SP-10 MK II has a motor assembly with a top plate and the platter is fastened to that top plate by 3 flat head screws. On my SL 1100A, the arrangement is similar but the platter simply rests on the top plate without any fasteners. I also have an SL 150 MK II and that is similar to what you describe in the 1200 where the platter is an integral part of the motor.
The question remains however whether these DD models remain perfectly concentric in response to stylus drag or are spun off kilter by their looser bearings structures. I think that was what TWL was saying.
I questioned him about this because it appears that my DD tables are not vulnerable in the way he described. Maybe they are.
I also have a Luxman PD 441 and it has a magnetic mechanism which reduces the platter weight on the bearing by 80%. Is this better or worse in relation to Tom's premise?