Hello Kevin, on the AS Thunder I use this leather mat with holes with excellent results. On the AS Final tool a leather mat from Pro-ject. It stops the ringing of the platter completely.
Knut.
Acoustic Signature Thunder & Final Tool, Technics SP15, Ampearl RE1030 Valve Phono, Ampearl Valve phono LCR RE2030, Ampearl RE1031, Tribute SUT, Aidas MC, Linn Akiva, DS Audio E1, Nagra VPS
Legat Audio SETA E130L SE, Legat KT88 SE , K&T Donar, JE Labs Open baffle with Philips 12202, BK elec SUBs P12 & XXls400