Thoughtful exchange above from many posters and valid points, including some helpful direct experiences shared. In my personal experience, the Technics Sp10Mk2 will indeed benefit from the use of an appropriate mat, the exact type and subsequent composition will depend upon the listeners tastes. I for one, enjoy both Copper based mats (i.e.. Micro Seiki CU-180) or a composite (rubber, or cork/rubber/leather) mat used in conjunction with an aluminum based mat, such as the Oyaide MJ-12. In fact, during testing, I found Copper based material to be so desirable, the result early this year was our manufacturing a brand new Sp10Mk2 composite platter consisting of stress relieved Aluminum + Copper. For those who may prefer certain playback characteristics of different materials, I am working on a design revision which will allow interchangeable upper platter combinations.
The material Delrin, solely used as a platter mat material, as suggested above by Mosin, we actually designed and manufactured for a brief period of time but production ceased immediately when the mats began to develop warping anomalies. Their musical characteristics I found to be pleasant, albeit slightly polite. A different type of Delrin composite based platter mat we are developing however, but the release date is unknown. Another issue faced when using pure Delrin is the potential for excessive residual static build up. I've yet to listen to (evaluate) the Boston Audio Mat1 or Mat2, however, the use of Carbon/Graphite seems logical and a good choice for material selection, given its rigidity and density. TTW Carbon hybrid record mats I have heard positive things about, although personally have not had the opportunity to evaluate at length, so I cannot comment.
Lewm, I wholly agree with your assessment of overtly heavy record clamps. In my experience, I have found that time again, they result in more degradation than good. This applies to all drives types mostly, with few if any known exceptions.
A quick word, comment rather, with regards to the Sp10Mk3. Having spent years designing plinths, playing, owning and testing this Technics model, I agree in that they are indeed a reference level analog playback machine and remain worthy of serious consideration. However, the secondary market prices for stock units, in my opinion, have now inflated to an extent which has made them less attractive an option than at one time in the not so distant past. It is for this very reason, that I continue to exploit the undeveloped playback potential of the Sp10Mk2 platform.
With respect to the forum thread poster, my apologies for straying off track of the original record mat subject.
