Hi, your Scheu platter and bearing are very similar to my Teres, which has had at least four rebuilds to get where i am now, so can I offer some opinions about plinth designs based on what I have found to work - and not to work?
These are. if course just a personal opinion and I have only been able to try a few combinations so there must be many other possibilities at least as good or better. Hope they might be of some use.
1 my first build was based on plywood layers with lead and sand filled compartments inside. I thought it sounded good until I changed it. In reality it wasbass light with less definition than I got later.
2 High mass alone is not necessarily good as it can just store and reflect energy. A composite material like Corian is one of the best solids because it is made up of materials of very different densities. It also machines with a router using cutters designed for Corian and looks really good (Nottingham Analogue).
3 My best result has been a high-mass base using constrained layer damping - in my case glass/aluminium like the Marantz TT1000. the layers must be very firmly bonded together. The aluminium transmits vibration, the glass constrains the layers and "kills" it. Tip - get the glass cut first and then make the aluminium to it; my local glass dealer only works to +-1mm tolerance!
4 An air-suspension base is easy to make using a bicycle inner tube, but it really didn't work well. When I changed to cone feet the differerence in detail and solidity was amazing.
5 Even given the really large mass of the turntable, when I re-used my original wood-based plinth as a second platform under the plinth, there was a major improvement again.
6 A screw- down record clamp really worked well.
There are some pics of this at various stages at:
http://www.william-reed.net/audio
regards, jeff
