Direct Drive vs. Idler Drive vs. Belt drive

@atmasphere,

WRT to platter mats, the concept that materials cannot absorb/attenuate vibration is not correct.  Very thin viscoelastic materials can absorb surprising amounts of vibration - the energy is converted to heat.  This article is an excellent example - https://core.ac.uk/download/pdf/36723450.pdf.  Note that just about any thin material that can stretch such as a PVC film that protects a metal plate can act like a viscoelastic material.

Also, materials - metals while known to have different vibration damping characteristics, is actually well documented - download a report from this site: https://apps.dtic.mil/docs/citations/AD0640465.  Aluminum while being cheap has good damping characteristics and cast aluminum (i.e. ATP-5) can be better than extruded (i.e. 6061), but cladding improves it and magnesium beats all - but magnesium has that small issue of being able to burn quite vigorously.  But, some tonearms such as those from SME are manufactured from magnesium and for good reason.

I have personally had excellent results from a piece of very thin leather (sourced from a craft store) about 1-mm thickness with skin side down to a VPI aluminum platter and suede side to the record.  The suede side is very dense - much closer to a felt-type material so that the record mates to the record with little or no air gap, but does not produce lint.  A similar type mat (but pig-skin) was once available and very well reviewed -https://www.6moons.com/audioreviews/hiraga/mat.html.  

Also, as far as the triboelectric effect leather can vary based on type and moisture (which it can absorb) with the following being the latest (2015) triboelectric series (download from this site) - https://www.nature.com/articles/s41467-019-09461-x.

Just some thoughts,

Neil

"I did different thing and it’s not just about mass, because the SP-10 MKII does not have additional layer of the different material on top surface of platter as mk 3 model so i just used Micro Seiku CU-500 to upgrade it.

As the result, the platter made from one material was decoupled by gunmetal mat (material with different properties and different resonance). This is more like upgrading mk2 model looking at next mk3 model. There was the reason why Technics decided to add another later on top of the platter. So i had a gunmetal between the platter and vinyl record.

I asked why you just replaced original platter, because every Technics platter is balanced and there is a stamp about it. I have no idea who made the platter you’ve been using, maybe it was a bad platter (i mean not as good as the original) ? Increasing mass on Technics platter with gunmetal mat was huge improvement, but maybe not just because we add mass. This is what i want to say.

And another example is Kodo The Beat turntable, based on Technics motor, look at the Kodo platter.

Also nearly all turntables from Artisan fidelity comes with their own copper mats on top. Even tweaked Technics MK3 or Garrard 301

Even if the platter replaced with thicker and heavier one those guys always add copper mat on top of it, just like the latest Technics SP-10R.

P.S. @neonknight I am interacting here not with you personally, but with audio subject that can be interesting for others. No matter who is right or wrong, it’s important to add some information and everyone can decide what he like more. "

@chakster 

The above speaks to the concept that I had previously mentioned of the platter being critically damped and non-resonant being a more significant contributor to sound quality than platter mass as a sole indicator. 

I appreciate your above post, its far less combative and judgmental. I hope we can proceed forward on a more civil discourse. 

With any DD that uses any sort of servo feedback to maintain constant speed, the feedback circuit was designed for a particular platter mass.  If you change the platter mass dramatically, it is quite likely you will do bad things for speed constancy.  Likewise if you were to change to a much lighter platter compared to the OEM one.  Now, based on reports of others and my own experiences, there apparently IS some leeway within which some perturbation of platter mass will not do notable harm to speed constancy, but since every manufacturer had a different thought on the feedback loop and how to have it operate, there is no general rule about how far you can go.  I also don't know whether to credit some of the reports one can read on this forum, if you search the archives. Nearly everyone who replaces a 1kg platter mat on a DD with a 5kg platter mat, sometimes more than doubling the total mass of platter plus mat, says how wonderful it is. To me this says more about listener bias than it does about the physics.  And I also don't agree that there is a linear relationship or anything near to it, between platter mass and SQ. Belt drives with 200lb platters do not excite me.

lewm

Nearly everyone who replaces a 1kg platter mat on a DD with a 5kg platter mat, sometimes more than doubling the total mass of platter plus mat, says how wonderful it is. To me this says more about listener bias than it does about the physics.

Why? The physics of the situation are obviously different, so why would you discount that?

I'm really glad to see so much information and ideas being exchanged here.
The point of my post is to get a general understanding of what each drive type might sound like or what people thought it sounds like, so it's good to hear opinions from many different people. I won't be picking just one turntable as I do enjoy having many options. At some point, I will be adding a DD turntable, it should be fun to experience all three drive types in my own system.
I do agree that there are so many different variables in a vinyl setup that contributes to the final sound from the stand it sits on all the way up to the record weight, so deciphering what is contributing to what is almost impossible.