Advise on TT Support Platform


Hello All-
  This is what I plan to do and would appreciate any comments on my idea. I have (soon to be delivered) a new VPI Prime TT and plan to place it on the 1st floor of my residence which has a hardwood floor. Under the floor is a 5' crawl space with dirt bottom, the house is supported on poured concrete footings & 5' poured concrete walls.

  I plan to drill a 1.25" hole through the floor and run a 3/4" dia. black pipe (gas line) through it. The base of the pipe will be sunk into a 2' x 8" dia hole and filled with concrete while the pipe is centered within the hole with .25" of clearance surrounding it (isolating it) from the hardwood floor. The pipe would further be secured with 3 wire stays on turnbuckles ( as an antenna ) to alleviate any chance of pipe movement. The stays would attach to the pipe near the underside of floor & anchored into concrete foundation walls, then tightened down. The top (terminal) aspect of the pipe would have a black iron pipe flange screwed onto it at the determined TT height.  A 21" x 21" x 3" maple platform https://www.dawnsdepot.com/product-page/dawn-s-depot-maple-audio-isolation-platform-aud21213-21-x-21-x-3  would be bolted to this flange, to which the Prime would set upon.

  Further, I would install the Symposium VPI Prime Footer Insert Kit https://www.highdeftapetransfers.com/products/symposium-vpi-classic-footer-inserts   More on that here also: https://www.thecableco.com/Product/Classic-Footer-Damping-Insert-Kit 

   I'm thinking this will totally eliminate any footfall problems for good and create a internal TT & external platform/TT vibration and resonance grounding pathway to handle those issues.

  So, I'm looking at this as if the vibrations and resonance energies within the TT and those of the platform will be conducted as if they were electrical in nature and simply being lead to ground and dissipated. A note in this regard, my T.V. antenna grounding rod was buried 6' deep in case of a lightening strike in contrast to my 2' concrete filled hole for the 3/4" dia pipe.

  The TT is essentially coupled to the maple platform, and the maple bolted (coupled) to the flange & flange to pipe, pipe to ground.

 Is this sound? or do I have it all wrong?
128x128robes
Congrats on your new TT and further congrats on your very inventive solution to vibration issues.

What you propose should work at preventing floor borne vibration from reaching your TT, but so would shelf mounting.  How do you know you have a serious footfall problem?
Sounds like a very good solution to the TT vibration problem. But, a lot of work. FWIW I use a Core Audio PlyKraft 3L stand with my TT, see my previous post on this subject. The stand sits on a suspended wooden floor. It doesn't matter what I do (high volume, dancing, nudging the rack etc.) the cartridge never skips and there is absolutely no feedback. Works for me and the Core Audio stand looks beautiful IMHO.

 I also have suspended hardwood floors. I use a VPI Turntable stand filled with sand. On top of that sits a 3" maple shelf sitting on spikes. This works really well for me. The stand filled with sand is very heavy and stable. 


Sounds like your TT will sway around like the Empire State in a storm. Why not build up a stone foundation under the table location and bolt the floor to that?
If I understand you correctly, there will be a mass cantilevered about 10 inches in each direction, supported by 3/8" effective steel pipe, a 27:1 ratio. Sounds unstable to me.

Noromance has a good solution. Even better would be to do exactly as you suggest, but on each of three or four corners.

But don't forget about rats and mice and ants and ... all around that pipe.

Just my opinion.