Turntable and Rack vibration control


Hi,
I moved from a Nouvelle Platine Verdier to a Loricraft Garrard 301. The big change with this move was that the Verdier comes with a terrific implementation of pneumatic suspension feet which kept the TT almost floating and hence great isolation from vibration. The result was always a noise/grain free playback and super clean backgrounds. With the Garrard, the plinth is typical custom made stacked birch ply with standard steel cones as footers. When placed directly on the rack the background is noisy, the images muddle up and overall music is not well sorted.

I do not expect the Garrard to be as quiet as the Verdier but I know it should not be this noisy either. In fact the Verdier also sounded noisy when I placed it directly on cones bypassing the pneumatic suspension feet. 

I use a Hutter Racktime rack which is not like an overbuilt audiophile rack. It is more like an open frame rack with lightweight supports. It is a bit like a Rega TT, not very damped or controlled. The rack has pointy steel feet which rests on brass spike plates (mine is an wooden floor). I guess this implementation is not sophisticated enough to keep away vibrations and let the TT play quietly. 

I am looking at two levels of solutions:
1. Replace the existing steel feet and brass plate with a quality vibration control footer below the rack
2. Replace the stock steel cone below the TT plinth with a better footer/platform.

I have tried Sorbothane, Squash balls kind of tweaks, while they reduce noise they slow down the music too.
I have also tried Stillpoints and Finite Elemente footers under the rack. They make the sound thin and metallic IMO. Platforms like Minus-K are too expensive so I have not considered them yet.

I am looking suggestions here, probably footers and vibration control devices that are more musically oriented yet well engineered like Shun Mook, Harmonix, SSC or something like an HRS platform ?
pani
I would first try to take the table off the rack and put it on some amp stand with metal cones or even simpler to put the table on a 2"-3" maple platform with cones under it. May not be convinient though and sure may not work. I have Nottingham sitting on 3" maple block with Boston Audio graphite tuneblocks under the block on the floor, the wooden floor in an apartment. I wouldn't want to dance or jump near it but walking is fine, and everything sounds right to me.
Great idea of the glass marbles and bowls, Geoff. Better than the wooden egg holder or metal concave drawer pulls DIYer’s have been using. If one likes the result, the professionally made roller bearings can then be purchased, for even greater isolation.
I just managed to borrow a set of Townshend Seismic pods under the plinth. The sound is totally in a different level. The grainy, noisy background is 90% gone and what I am hearing is a very open airy and free sound. That is with the deck plugged directly into the wall through a basic $50 power cord, so no electrical isolation yet. Whether it is the final solution or not is yet to be seen but it definitely confirms that isolation is the problem, not the deck itself. At least some breakthrough!

I have Townshend speaker bars under the speakers with great effect. You should try it also. Not so expensive and very effective (under Analysis Audio Epsilon). Concrete floor.