Vintage DD turntables. Are we living dangerously?

What is the theory of a heavy copper mat? I can see adding to the flywheel effect, but that isn't how most dd turntables including the 101 work. I can see it as a EMI shield, but the TI material is probably better as it was designed for that purpose and it weighs relatively little. There has tone better mats for draining record vibrations (I like the achromat) and sorbothane is probably better at damping a ringing platter. So, what is it?

I don't know what it is Aigenga.......but the Cu180 improves both frequency extremes in a consistently audible manner :^)

There are possibly several things going on with a copper mat. My Final Audio has a 4.5kg copper mat - the copper mat in conjunction with the 15kg aluminium platter provides bi-metallic damping, tapping the platter with and without the mat demonstrates the effectiveness, and is also a calculated energy path for the stylus/record by the designer to provide a mechanical ground. All other mats I have tried are significantly inferior on this particular tt.

Audpulse, thanks for the rey to Audio Fidelity - they could be just the right guys to rewire the arm on the L07D I just acquired from Lewm!

Couldn't find much info on the delrin mat on their website, I will have to look around for similar mats. On my Micro I use a similar product which I got from Germany here: http://www.ebay.ca/itm/Plattentellerauflage-aus-PLEXIGLAS-5mm-stark-D-293mm-/370183497535?pt=Plattenspieler&hash=item5630a7e73f#ht_3509wt_905

This an acrylic based compound that works best on the SX8000, noting that this stainless steel platter, does not require damping, unlike the Micro RX5000 which rings like a bell. I suspect I get better results from my SAEC and Cu-180 metal mats on my other tables because they are acting as damping controls. I have experimented with a cork / rice paper /cork sandwich and that works quite well too. All of these seem to give a more lively outcome than rubber. I have not experimented with leather mats, but am intrigued on that front.

One thing is clear, on all my DD tables, the SAEC SS-300 or Cu-180 are the winners. The worst ever mat I tried BTW was the Kenwood/Trio ceramic mat - it completely destroyed the timing of anything played on it - ughh!

This whole topic of record mats can be a different thread, I have never cracked it .......

the ebay link did not translate, search for acryteller as the seller. An outfit in Germany that sells a whole bunch of platters, mats, weights etc.