I have another variation of Dgarretson/Cmk ideas combined but with spikes or isolation bearings between the maple on top and the granite on the bottom, and TT directly on the maple. That will keep the design coupled. I have mono block tube power amps on an oak suspended floor adjacent to their floor standing full range speakers in this composition and it sounds great. I would only caution that springs or racquet balls create a additional suspension (uncoupling) if the Voyd TT is suspended, thats usually bad news. If it is not, what is the logic behind adding a suspension to a non suspended TT? It may well defeat the sound qualities of a rigid design. Why not buy a suspended table in that case? Which I realize is not your consideration, Im speaking rhetorically. Gentlemen, I mean no offense, I only wish to raise some questions to help us (maybe) all better understand the task at hand. Best of luck in any case.
Happy Listening!