Aluminium/ steel platter mats

[AJSki2fly]

Cheers, I will have one to try soon, the theory behind it is interesting.

I find it interesting that some of you are using aluminium and/or steel platter mats. gwernafield has been doing various investigation into ES (electro static) and I have some knowledge of it due to my repair work, and have checked some things out about materials prone to ES build up. Aluminium definitely is, and Steel can but less so.

[krugdoktor]

The best mat I ever had was a SAEC SS 300 aluminium mat on top of a SDS isoplat mat on the original Techie platter. The SDS damped the (very resonant) Techie platter perfectly and the SAEC provided the interface between record and platter.
Unfortunately the center spindle of my new Technics 1200G is not long enough for the „sandwich“, and the SAEC alone on the 1200G platter does not sound better than my Oyaide BR-12. Interestingly the Oyaide was far behind the „sandwich“ on the original Techie platter, so I think: the platter has to be inert (if not it should be damped) and the platter mat should only provide a perfect interface between record and platter!
Btw the SAEC has a very rough surface (anodized?) so it „grips“ the record especially when a record weight is used.
PS.: I never had ES issues with the metal mat!

[YNWaN]

I’ve written loads (tediously so I’m sure) on mats and record clamps/weights over the years. One manufacturer even used a collection of my own forum quotes to justify their design! Anyway, the vast majority of turntable bearings (all those mentioned in this thread) are a shaft running in a journal and supported by a thrust pad. The entire mass of the platter is therefore supported on a point running against a thrust pad. This gives a very small contact point and therefore low noise, but a very high point load/pressure. Depending on the mass of the platter a metal mat can add a significant extra load (up to 25% potentially). The same can be said for record weights where very heavy ones are available. The nature of these point load bearings is that one part is trying to drill its way through the other and the more pressure applied the faster, and more efficiently, this will happen. In reality it is very unlikely that one will actually wear through the other but it is certain that wear will be accelerated (contact wear cannot be avoided) and as wear increases so does contact area and so bearing noise. I promise all this is basic engineering fact - there is no free lunch and everything is a balance of compromises.

[YNWaN]

Putting aside weight, mats are a whole issue in their own right (as are clamps and weights). The first thing to consider is the key purpose of the mat, is it to support/damp the record or damp the platter from ringing? Mats that are good at one are rarely good at the other. For example, a thick rubberised mat is great for platter damping but awful at damping a record - at least awful in terms of linear damping a record and results in some frequencies sounding heavily over damped (slugged/stodgy) compared to others.

[Pharos]

"the platter mat should only provide a perfect interface between record and platter! "

On that basis I have bought a sheet of 3mm PVC sheeting and made a mat for my Linn, having been fed up with the felt which encouraged static and hence dust, and was more of a risk to the stylus also.

My reasoning was that the felt was very non dense, and the PVC is more so, probably nearer that of the record and the aluminium platter, thus the mechanical impedance will be a greater match.

Cleaning will be easier, but I haven't tried it yet.

[Boussven]

On the Puresound Tenuto mat:

personally I haven't heard a negative as of yet and I have had mine in for over a year.

Dave Cawley from Sound Hi Fi prefers the Oyaide BR-12 on his SP10 Mk2 restaurations.

Some others say the weight will wear out the bearing, on any turntable. People with technical skills that I trust, reinforce the bearing of the Garrard 301 with an extra thrust plate, when using the Tenuto mat.

Any thoughts on that?

[Bigman80]

On the Puresound Tenuto mat:



Dave Cawley from Sound Hi Fi prefers the Oyaide BR-12 on his SP10 Mk2 restaurations.

Some others say the weight will wear out the bearing, on any turntable. People with technical skills that I trust, reinforce the bearing of the Garrard 301 with an extra thrust plate, when using the Tenuto mat.

Any thoughts on that?

No, not really.

I suppose it's entirely possible that having extra, unplanned weight could cause a bit more wear on the bearing but up untill right now, I haven't seen or heard of a single SP10 with reports of excess bearing wear from using a heavy platter mat.

What's more, there's a theory that is possible for almost everything but whether it ever actually pans out is another thing entirely.

Mr Phonomac has used one for years and as he is the man to know, I trust his opinion that its fine.

If anything I'd be more concerned with the motor needing to shift more weight than it was planned to have in the conception of its design. I am reassured though that there is more than enough capability in the motor to handle this without stress.

The Technics Guru, Mr Phonomac would be the guy to ask and to be honest, if he says it's fine (which he does) then it fine. No doubt about it.

[karma67]

i would have thought its pretty obvious that if you add another 5 kg to the platter the thurst pad will wear quicker than if you dont add 5kg.
with that said it doesn't bother me.