What are good turntable acoustic damping materials

Suspension tables may not respond favorably to additional dampening. IMO, based on listening tests my LP12 didn't like a non-felt mat or the use of a clamp. Dampening the motor housing may provide some benefit but I have yet to try it but plan to. Geez, I'm probably going to take a hit on this, but those tables that over-use lead don't get my toe tapping in spite of some benefits such as a blacker background. There is an eBay seller that has a number of dampening devices for a Linn that seem interesting. I'd love to read an Audiogon review of his products. I'm also anxious to read what Bright Star Audio has to say. I've got an open mind on this topic.

Bright Star Audio,

Please enlighten me without too much tech talk regarding these words you posted above:

"Felt will damp some ringing and resonances present in the structure of the Thorens but it will not be as effective as more absorptive materials (that are typically more massive). The objective is to convert the mechanical vibration to another form of energy that will not affect the musical signal. Converting the mechanical vibration to thermal energy (heat) is very effective if the transfer is done as efficiently and quickly as possible."

My simple mind tells me that a suspension attempts to isolate the record surface/stylus from vibration and the felt mat is just an extension of that design philosophy. By using an absorptive mat aren't we more or less coupling the record to the suspension and thus defeating the principles of the design? Or, do you know of a mat that acts on absorption without transfering energy back to the platter?

If you know of such a device I would be happy to audition one and write a review. Another question. Are you saying that the platters from either a Thorens or a Linn actually ring? Having owned both brands of turntables in my nearly 40 years of spinning vinyl I've never heard any ringing.

Thanks.