Turntable Isolation

Magnetic levitation is the way to go. Not that difficult to setup nowadays; the new ultra strong magnets are not that expensive.

Then just a couple steel plates and you are in business. A little foam or something on the sides to keep the suspension aligned... Abso;ute 100% isolation.

that isn’t correct. First of all, your design means there is some physical contact between the plates, if not the top goes shooting off to the side.

The other thing is it is not a magic carpet suspended in air. There is a force from the lower magnets pushing up on the ones on the top plate. Shake the bottom and the top reacts. It is NOT 100% isolation. it may be damped, but it is absolutely not 100% isolated.

and lastly, there is the question of leveling it. If the load on top is not symmetrical it will tilt. Not good for a turntable.

Solid Tech - feet of silence will solve your problems- worth every penny!

@polkalover I am a advocate of Solid Tech 'Feet of Silence'.

I have these as footers that superseded all others used on a particular weight of TT. Those who I have loaned these to but wished for a little more weight to be supported have fabricated their own suspension platforms based on the design/SME Design.

I have heard these DIY Version in use against the users previous footers and their DIY Types of suspension platforms, and am totally convinced that everything the   ' 'Feet of Silence'  can create as a sonic improvement/attraction is present. .

If a Densified Wood was used as the Platform I am certain these DIY versions will have been a further improved design.  

If your problem is a floor that moves when you walk, get yourself a turntable wall-mount.  Because you have a VPI Signature 21, I'd recommend going to a local shop that does metal fabrication and have one made for you.  Those VPI tables are very heavy.  

You'll need to get a handyman to attach it to your wall with lag screws into studs.  This will need to be an extremely sturdy platform due to the weight of your table.  Keeping in mind that this is a $10k table with a cartridge to match, spending a few hundred bucks shouldn't be a big deal.  You want to get this right.

A wall mount completely isolates you from anything your floor is doing.

Going a bit further than what @elliottbnewcombjr recommended, you can go with Mapleshade’s complete vibration control system.  A bit much visually, but I have found it to be effective, both in protecting from footfalls and cleaning up the treble at higher listening volumes.  Also considerably cheaper than the Townshend or some other solutions.

https://shop.mapleshadestore.com/Vibration-Control-Systems_c_23.html

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