How to best isolate TT from vibration?

Wall-shelf. Target makes the Volkswagen of wall shelves --Available at Audio advisor, and other fine audio retailers ;--)

I do agree w/ Newbee's exception: If you have a concrete slab-on-grade floor (or a 1 foot thick steel-reinforced floor in a hi-rise or loft,) then a stout rack (like a Billy Bags) spiked right into the floor will do it (or for the cost of a few concrete blocks and some mortar, you could build your own TT pedestal for pennies!

I also think unsuspended tables are the way of the future ;--)

I don't have Newbee's faith in jacking joisted floors. Which isn't to say that it can't work. It's just that a lot of the existing floor's construction details have to be just right.

Tips about wall shelves:

Mount them on any masonry wall, if it works out OK for you in that location.

Second choice, an outside wall -- heavier studs and thicker surfaces (more mass -- less vibes)

If you're in a new, cheap, tract house, on an inside partition wall -- don't despair. Wall shelves are usually 2 stud spaces wide (16" + 16" = 32") Get a 48" wide (4 ft) by 2ft high by 1" thick piece of Scandinavian plywood (the kind with many pretty laminations, like used in furniture), finish it natural or to match the wall and lag bolt it to four studs (16" + 16" + 16" = 48".) You can mount the TT shelf on the plywood panel with lag screws, but if you're really cool, you'll pre-install T-nuts on the back side of the panel to receive bolts thru the wallshelf after the panel is mounted to the wall. It'll look great and be stiff as a board (did I say that?)
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Seismic vibration is at too low a frequency to be audible, and too low in amplitude to cause mistracking (unless you happen to be in an earthquake!)

If the problem is ground transmission of things like trucks, trains, or military ordinance (very) nearby, you'll be needing to soundproof/isolate the whole room, so the TT issue will take care of itself ;--)

Wall mounting is still the best solution.
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Good show Bill! LOL

(Architects always speak the truth. If we lie, the roof collapses!)
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