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
Sometimes you have to take a step back and reconsider your
options.
I certainly give you credit for creative thinking but as a few already
pointed out stabilizing your floor structure is straight forward
and cost effective. My method also.
Proceed upwards from there.


I am on hardwood pine with sub floor, suspended above a basement. Rather than industrial overkill, I did nothing to the floor. If you want an electrical ground, you get that when you connect the TT.  I have a quality equipment rack that provides some damping. The rack is directly behind the right speaker, like three feet. I then mounted a maple slab from:

http://www.mapleshaderecords.com/

Your Dawns Depot is a cutting board. I've had one and sent it back. The Mapleshade slabs are made by audio people for audio people. It's not a cutting board. I have a 4 inch one under my VPI Prime Signature and I am very pleased with the damping as well as the warmth of the maple. The four inch is best, but the two inch will do quite nicely as well. Cutting boards have more pieces glued together, the slab is made of 4 inch blocks so the damping is better.

Good luck on your floor rebuild. Btw, what will you do when you sell the house?
Your anti-footfall solution is massively engineered and will no doubt work. Far be it from me to discourage such an innovative & effortful concept.

However, I suspect the following would work just as well. This is something I planned to do based on a product that used to be sold in the '80s (for all I know it still exists):

1 - Using any wood of your choice (3/4" thick stock or plywood), build a study open-topped box ~2 ft wide X ~ 5-8" tall 18"-20" deep (exact dimensions depend on outside dimensions of your new prime, measured from outsides of foots or other support structure). The end result will look like a wide/relatively thin box laying on one of its large surfaces--but lacking the parallel large surface to "close" the box

2 - build a sturdy 3/4" thick "floating platform" (single piece of wood) that is sized ~1.5" smaller than the outside dimensions of your open-topped box. This piece of wood will "float" on top of the box, representing an approximation of that missing top surface

3 - fill the box w/play sand to w'in ~5/8" inch of the top. 

Just place floating platform on top of sand; then the Prime + any supporting footers/structure goes on top of the platform. This design pretty thoroughly isolates the outside world from the Prime (ie, any non-airborn vibration that might hit the prime from below). If the platform or structure on which this new box rests is itself well made & isolated (ie, steel cantilevered structure attached firmly to wall studs for wall-mounting)--the isolation should be quite good overall.
An interesting project.  To have a great TT you need great speed - easier said than done.  You also need great vibration control - also easier said than done.  No wonder the high end is so expensive.  There are may vibrations.  Most of them are like germs - you do not see or feel them but they are there.  To make a list: 1. Ambient vibrations in the room 2. Footfall. 3. Sound waves from the speakers. 4. Stylus colliding with the vinyl. 5. Friction of the bearing on the thrustpad.  They are all deadly because they get magnified some 10,000 times by the time they come out of your speakers.  Your solution will address 1. & 2.  My advice is to not forget the other causes of vibration.  
I myself do a little bit of this and little bit of that: Aftermarket feet ;(Isonoes); a PEEK (species of teflon) thrustpad; Mass (granite slab); Platter Damping (epoxy under the platter, quality mat, dynamat on unseen parts of the chassis).  Finally those vibrations that cannot be reduced or damped are 'tuned' in an attempt to sound benign.  So I use ebony - they make oboes and clarinets from the stuff.  Ebony stabilizer, ebony armboard, and ebony headshell.