Isolation Platform for my Sota Cosmos?

How about just replacing the factory feet with Stillpoints Ultra SS or Ultra 5?

Feet, spikes, pucks are band-aids. Take JWM's advice and hang it on the wall. It's the best and least expensive way to isolate a TT.

SYMPOSIUM is an isolation platform not feet or a wall shelf however it can be used on a wall shelf.

I had a serious vibration and acoustical problem, because my TT platform rested on a suspended floor (i.e.-not concrete, but joists) I tried mounting a platform on the wall, but still had problems. I finally suspended my table platform out from the wall using heavy duty springs in 4 places. The platform doesn't touch the wall or floor and the cables that do touch the floor and wall are isolated by springs. The platform is bubble level, yet it is suspended. I have a friend who hung his platform from the ceiling accomplishing the same end.
People who have slab floors are fortunate indeed. Ya have to work with what ya have.

THE SOTA FLOATING SEISMIC PLATFORM http://www.sotaturntables.com/engineering.htm

The lofty goal of Environmental Isolation resulted in the development of SOTA’s unique sub-chassis system, the Seismic Platform. Environmental Isolation means isolating the moving platter from all the physical and mechanical threats (footfalls, room resonance, air-borne waves, etc.) that will ultimately disrupt the retrieval of the information contained in the record grooves.

Key to the SOTA floating seismic platform is the theory of basic mechanics that tells us that the motion of a moving mass will be most constant when supported by the inertia of a greater mass. In the SOTA turntables, the 12 pound platter is successfully isolated from the environment because of the enormous mass of the 22-pound sub-assembly. To further enhance isolation, the sub-chassis is constructed of self-damping materials (again, constrained-mode construction techniques), with lead providing mass and energy sinking. Each sub-chassis is individually balanced at the factory, complete with its matching platter attached.

The unique SOTA turntable sub-chassis is then hung from a four-point spring suspension (spring utilized on the Sapphire, Star, Nova and Cosmos), giving it all the stability of four pendulums at rest. The four springs are damped to absorb high frequencies and decoupled from the sub-chassis to minimize energy transfer, fixing the suspension frequency at 2.5 Hz. By "hanging" the sub-chassis on springs, gravity stabilizes all external energies due to the centering tendency of the pendulum motion, rather than pulling the mass off center as is the case in the typical "compressed" spring suspension. With a four point suspension (made of four springs placed equi-distant from the center of gravity) and four equal masses (one of which is the adjusted mass* of the tonearm), the SOTA turntables offer a level of stability that can only be achieved with a constantly-balanced- mass system. No matter the tonearm, mass is constant, motion is predictable, and the end result is once again a system that achieves our goal of Dynamic Stability.
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