A Copernican View of the Turntable System

The Mitch Cotter that I'm familiar with had a sprung suspension just like a Linn, only more springs and controlled better with foam inserts, no pneumatics involved.
The main thrust of his design was to remove all the extraneous crap from the direct drive ( motor covers and controls etc ) which removed resonances, and the use of an extremely rigid and inert aluminium/polymer laminated chassis to bolt BOTH the arm and DD motor drive.
Some great ideas embodied in that design in terms of energy control and maintaining a closed rigid loop between platter and arm.

Banquo363,

Many thanks

As always...

Dover,

Yes, and thanks for helping with my ongoing considerations, research and experimentations. Of course, Cotter's floating (aluminium/polymer laminate) baseplate and attached platter was decoupled from the main chassis. My point was that the polymer fillers and springs that sat against the baseplate served a similar function (albeit in a far less efficient way) to the pneumatic footers against the bottom of the SP10 regarding resonance control.

I didn't discuss the dismantled motor that many have already considered regarding Kenata's design etc. I do feel that the potential gains of that aspect of Cotter's approach are accommodated in a simpler way by the already noted plinth-less and pneumatic support approach, however.

Much more reflection and experimentation to be had but progress seems promising.

As always...

Lewm,

All too confusing an analogy for me. The SP10's peritoneum would surely be the motor case rather than the additional plinth!

Designs seem to vary but operational excellence needs to be assessed in the light of the object and function under consideration: 'just as' arthropods function well with an exoskeleton but I function best 'keeping mine' internal.

I'll just press on with my efforts to discover how the SP10 and its associates function best. Who knows, when all is said and done, I could end up sharing your anatomically grounded perspective. Time will tell.

As always...

Dgob, Sometimes I go for humor ahead of substance. Just kidding. We all know where I stand on the issue of plinths. I have done the work to reach my conclusions, so I feel ok as regards my own preferences and my own system. However, I am beginning to think about an inert plinth that provides a lot of mass mostly under the platter/motor assembly, so there is a minimal "deck" extending out around the platter periphery. Then a pod for mounting the tonearm, like the ones some of the guys have built, that would be firmly mated via a structural member, back to the main plinth. A few commercial products are built that way. I do not back off my contention that a closed loop connection between the tonearm bearings and the tt bearings is desirable, as Dover mentioned.