Rockitman posted some pictures in another forum of the Clearaudio Master Innovation "magnetic-drive" turntable, ie, a belt-drive turntable's platter is driving a turntable above it via magnetic coupling. It's a doubledecker!
Clearaudio Master Innovation pix
It's a noncontact approach. A belt is compliant and so is magnetic force so it's a double compliant system. Why not simply drive the platter with magnetic force using some ironless & coreless coils underneath it and tweak the magnetic force/compliance via precision electronics..... oh, voila, it's a coreless direct drive motor. Oh my god, it's a direct drive turntable! Who wants that?! :-D
P.S. My concern with the Clearaudio approach is the top deck's bearing. To allow the driven platter underneath the top platter the bearing shaft has to protrude down to hold a platter so naturally it cannot allow for single ball bearing well and my guess is a type of angular contact bearing --similar to the EAR Disc Master turntable-- that has more contact point than a simple one baller. To gain no contact on the platter you have to add more contact points on the bearing. You gain something, you lose something. No free lunch.
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