Isolation Platform for my Sota Cosmos?

I have a suspended turntable and recently bought a self-leveling Vibraplane to place underneath it. The improvement was clear. I then ordered a custom steel ballast plate which weights 136lbs. This is large enough to also place my motor controller on it. This increased the performance even more. I have a very solid, rigid DIY rack with lolli columns in the basement supporting the floor under the rack, so there is no bounce to my suspended wood frame floor.

Proper, serious isolation solutions are a very effective way to improve turntable performance, even if the turntable is a suspended design. Photos can be viewed on my system page.

Tonywinsc, As my system has improved, those sounds swooshing around in an oval patter have moved from above the plane of the speakers to now where they are circling above my head. I have not gotten the oval to go completely behind me yet, but it is indeed an amazing effect. A bit like helicopters in a big Summer Blockbuster movie. This is an LP that continues to sound different as the system changes.

Geoffkait, that is an interesting post. I never really considered that. I may try to lock down my SME suspension and listen to the result. The other alternative is to tune either the Vibraplane or the SME towers to different frequencies. They are adjustable, but I don't know how to measure the respective resonant frequencies. Thanks. One more thing to play with.

The SME suspension towers are heavily damped, so pushing down on the plinth does not get it to oscillate. Likewise, the Vibraplane is fed by a compressor, so as soon as one corner is pushed down, the air bladders immediately fill up and so it does not oscillate either.

I have not tried to defeat the suspension of the SME and listened to it on the Vibraplane. I only compared the table with and without the Vibraplane, and it is better with the Vibraplane inflated. The motor controller isolated on the Vibraplane also makes quite a difference.

Thanks for your suggestions. BTW, I thought that if they are 180 degrees out of phase, they would cancel, and it is only when they are in phase that the cycles amplify to cause problems.

I suspect all is fine, because I have never seen either move and the sound has never been better. But I wonder if the isolation is redundant. I'm going to try to defeat the isolation on my the SME towers this weekend and give it a listen.