Direct drive/rim drive/idler drive vs. belt drive?


O.K. here is one for all the physics majors and engineers.

Does a high mass platter being belt driven offer the same steady inertia/speed as a direct drive or idler drive?
Is the lack of torque in the belt drive motor compensated for by the high mass platter. Object in motion stays in motion etc. Or are there other factors to take into consideration?
I am considering building up a Garrard 301 or Technics SP10, but is it all nonsense about the advantage of torque.
I am aware that the plinths on these tables can make a huge difference, I've got that covered.
My other options would be SME20 or Basis 2500 of Kuzma Stogi Reference etc.
If I have misstated some technical word, please avert your eyes. I don't want a lecture on semantics, I think everyone knows what I mean.
Thanks in advance.
mrmatt
Dear Ralph, I would have to agree with Axel. Platter mats (pads) have received LOTS of attention during the vinyl renaissance, both in the aftermarket and from turntable manufacturers. Just do a search of any website that features products for vinyl reproduction, and you will find dozens of candidates. In fact, there are too many different choices for any one person to evaluate. Materials include felt, rubber (or some variant thereof), sorbothane, carbon fiber, graphite, copper, other metal types, dots (made of cork, felt, what have you), and combinations of any of the foregoing, plus no mat at all. I guess what you are saying is that only the one mat made in small numbers and sold only in Minneapolis area and on early SOTA tables is really proper. Can you reveal what it is made of? By the way, many would agree with you that the mat should take energy away from the LP and therefore should be made from a material that is similar to vinyl. So why not vinyl?
If the speed of a turntable is off by 1%, which can happen to some Rega tables, you think a fancy platter mat(I am sticking to the term "mat" instead of pad just for conventionality, why change now.) can improve that? Enough said.
Lew, I myself think that is a good idea. I agree there are a lot of platter pads out there, as Axel says, its just that most of them are a joke. If you are going to make a decent pad, it should use materials science and physics- like understanding how vibration travels through materials.

Keep in mind that the stylus exerts tons of pressure on the LP. Yeah, its only a 1 1/2 -2 grams but the stylus is tiny. The result is that the LP depresses, just like ice on a frozen lake does when a car drives over it (of course, we probably see more of that up here in the frozen wastelands).

So the mat cannot allow the LP to sag- it has to stand up to it. And it has to do that while controlling resonance. That is why this is such a tricky issue- and why so many platter pads are really not even close.

I'm sorry that this pad that I and a few others have is not in production (IMO/IME it was the biggest advance in LP reproduction when it appeared). That it contains lead dust likely has a lot to do with it :)

Warren says he can't get some of the materials anymore. He also said it was very labor intensive- the materials had to be combined in the right order and with correct timing. He used a special oven to cure it. I have seen a few examples come up for sale- the last one I saw went for $1200.00. Based on that I would guess that there is a budget for someone who wanted to get serious about this.

Obviously not every table could manage this thing- it weighs about 5 pounds.

Since there are only a very small number of these made before SOTA got the rights to it, there are only a few people who have heard what it does and how profoundly it affects things. However my point here is not that I have this thing, but what it taught me: that **only** when the platter pad and platter issues are reduced to a common denominator can you have an intelligent conversation about drives. This assumes that the 'table is otherwise on speed and working right, with no 'measurable' speed issues. IOW I suspect that many here are describing other differences and ascribing them to the drive when there are more fundamental issues involved.

I cannot tell you how many times I have seen people come into a room and upon hearing something they like, immediately ascribe it to the speakers, taking nothing else into account. I believe this to be the same phenomena, since I don't know of a decent production platter pad. If someone can point me to a pad that has the exact same hardness as vinyl but it otherwise completely dead, I'll immediately make an exception. Any takers?
Dear friends: Atmasphere is spot-on in the subject. The fact that almost no one of you already have that kind of experience does not means he is wrong and you are right, please let me explain on it:

in the deep research that we make ( and still doing. ) in our self tonearm design one of the main factors for achieve our main tonearm target ( a Universal tonearm where any cartridge shows its best like in no any other tonearm. ) is the build tonearm materials especially at the headshell/arm wand.

Testing different available build materials we can't find the one that help totally to achieve our main target so we have to start a whole build material research that bring us to " build " by ourself the main tonearm build material: this is a propietary blend.

Well this propietary blend material help us to achive our tonearm main target.

Through all that research that take us several months we learn the critical importance that have the build material where the cartridge is attached ( tonearm ).
The cartridge is like a very sensitive micro that detect tiny very tiny ( microscopic ) resonances/vibrations/distortions that you and me are not aware even exist and that affect the quality cartridge performance in almost the same way between the TT plater and the cartridge.
Today I can say that that tonearm build material makes a paramount difference in the cartridge performance.

Well, I ask my fellow Guillermo why not try that same tonearm build material in a TT mat/pad and VOILA!! the differences ( in six different TT's. ) in dynamic, tonal balance, transparency, soundstage, focus, top to bottom coherence, in any single performance parameter improve ( not only different but better. ) like night and day!! lowering ( almost disappearing. ) distortions/colorations level to almost CERO!!!!

I can say that this is a unique experience and that's why I understand in a precise way what Ralph posted about that almost no one of you can't understand till you have/hear that experience.

For months and in different threads ( mostly on tonearm/TT's related subjects. ) I posted ( anyone can read it. ) the critical/crucial importance of the tonearm/TT build materials that makes a difference for the better, till today no one ( but Ralph ) gives the right importance to this main factor and you can see in this thread: everyone speaking ( one way or the other ) about motors, belts, bearing, drive system, etc, etc. I'm not saying that all those factors are not important certainly are but till today no one ( tonearm/TT designer/manufacturer address seriously ( I mean in the right way. ) the item build materials.

I know ( Lewm. ) that exist several commercial mat/pad options but no one is near of what Ralph or I already experienced and know about.

I know too that is a little frustrating for almost all of you don't have an opportunity to hear that unique " audio experience " but if in anyway serve for anyone of you my audio system is OPEN for you anytime you want it.

In the midtime we are almost finishing our tonearm design and starting our TT design ( with that propietary blend material. ) along a cartridge.

Regards and enjoy the music,
Raul.
Wow, what a great discussion. As a Galibier owner, I can't wait for RMAF to audition the new motor/controller.

I tend to agree with the opinion that while each design has its particular set of strengths and weakness (resulting in a signature sound), excellence in implementation is critical. The Saskia is a very different from my Galibier and each have their own sonic signature, however, I would be happy with either. With a well-designed system, it's not 'better or worse', it's a matter of taste.

One additional variable that hasn't been addressed is production variability. Since many of the high end tables have limited production runs, I would guess that there is variability between each table produced by a given manufacturer.

My wife and I experienced a similar phenomenon when we purchased our piano. After months of auditioning, we decided we perferred the Steinway sound. We spent many hours over two counsecutive days, auditioning 18 Steinway L models. Each piano had the Steinway sound, but every one sounded and played a little differently. On the 2nd day of our auditions, Van Cliburn was visiting the dealer's showroom and he played each of our finalists. That really brought out the individual personality of each piano. (Analogous to the difference between having your analog system set up well versus set up perfectly).