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 think Minus K isolation would help tremendously, not cheat but very effective 
and no compressor needed.


I may be wrong, but @pani is trying to walk a fine line here- too much cushion and he loses the immediacy that these tables are known for (and the reason he presumably switched from the Platine Verdier, which is highly regarded table). I can’t really extrapolate my experience because I use a very high mass turntable, but I was bedeviled by a springy wooden floor when I lived in New York and wound up with another historic house in Austin (which actually has nice sound for reasons that go beyond this thread). Initially, I had a Finite Elemente stand for the table, but it didn’t do a very good job at isolating footfalls (I’m not sure it was intended to); I eventually had an HRS platform made for the table, and that still needed more help to fully isolate the table- using these big chunks of sorbothane under the legs of heavy mahogany antique prayer table/HRS platform/turntable.
When I moved, I didn’t have the luxury of such space (that prayer table was easily 10 feet long and heavier than XXXX).
I kept the HRS and did buy the big Minus K. It certainly solves any footfall problems. I know that @pani said he doesn’t want to get that spendy. For what it is worth, I reinforced the floor in the area when the front end gear is located- using double sheets of marine plywood, mass loaded vinyl sandwiched in between and topped with a piece of barn stall mat- the stuff you see in gym weight rooms. It isn’t springy, but it will take some punishment.
The table is on a steel welded frame supplied by Minus K- that frame was actually pretty cheap- under a grand, with a nice phenolic table top, that can be bought separately.
I think part of the trick with these things is to load them near their maximum, and perhaps that’s how @pani can straddle the line between too soft and no effective isolation. The Newport products look fairly cost effective.
I have no doubt that these lab style isolation devices change the sound of the table. But, in my case, it was a choice between that or not using this table (too heavy to wall mount effectively-- I even had a structural engineer here at one point for other work and he wished me luck).
Hope you get it sorted. If Ralph’s high mass solution works on an old wooden floor, perhaps you don’t have to go to these lengths. But, without the Minus K, it was still a lot of work to immunize my table from footfalls without such a device when I had it set up in back in NY.
Thanks guys,
I need to clarify few things. My floor is concrete but with wooden parqueting on top, so there are no foot fall problems.

I am just looking for a good vibration control for quieter playback. One of the achilles heel of using turntables like Garrard is one is on his own to handle isolation of the TT. The plinth is mostly any of the small DIY outfit and there is no scientific method being used to create a plinth or platform for the Garrard to be hooked on. It is quite unlike a TT like Technics SP10 or say a VPI where all these things are done up for you at the factory so it can be played back right out of the box. 

Till now I have tried to keep things simple with my garrard by using a good multi-layer birch ply plinth and using some cones to rest it on the rack. But it is now getting painfully clear that this is not a very well-sorted system. The noise floor is high, the images are grainy, the air and tranquility is missing. When I tried some softer footers, it did wonders to the sound by bringing back the air and lowering the noise floor, just that it was again not a full proof solution.

I wonder if I should get something like an HRS platform which is scientifically designed and as is a complete solution of sorts. Suggestions ?
Here’s a little trick with marbles. You need three large size glass marbles and three glass or ceramic shallow bowls. The ones that are used as bases for those small incense candles are perfect. Then all you need is a glass or ceramic top plate which is placed directly onto the three marbles. Then balance everything with the component sitting on the top plate so the marbles are centered in their bowls/cups but free to move in any horizontal direction. For this to work correctly there can be no cables pulling on the top plate, etc. so the top plate and component are free to move very easily.

@pani- you said "When I tried some softer footers, it did wonders to the sound by bringing back the air and lowering the noise floor, just that it was again not a full proof solution."

What is missing, in your estimation, to reach the 'full proof solution"?

I would think some of the 301 users with various plinth set ups ought to be more help to you. 

Bill Hart (f/k/a Whart)