Excellent guidance and insights from Pryso. Always a pleasure to see coherent thinking. It's more effective to thoroughly understand the problem(s) you're trying to address and select solutions which address them than to try stuff willy-nilly... or to do nothing.
I could not afford a Minus K, but I did want to isolate my 90 lb., unsuspended TT from floor-borne vibrations, particularly as the floor is suspended wood (though well built and sturdily framed). In trying relatively inexpesive solutions, one finding was consistent and clear: the closer the isolation element was to the cartridge/tonearm, the more deleterious side effects were audible.
High mass, unsuspended tables are rightly prized for their massive dynamics and good low frequency response. Light weight, springy tables simply can't compete in this area because movements of the cartridge and arm induced by groove modulations can actually wag the table. High mass tables resist this, but will be susceptible to floor-borne vibrations, including those from the earth itself, passing traffic, etc.
Placing isolation devices immediately below the table did lower the sound floor, as expected, but it also diminished dynamics and bass response. In effect, I'd converted my unsuspended table to a suspended (if massive) one.
What to do? Increase the suspended mass by moving the isolation devices from beneath the table to beneath the stand that supports the table. My TT sits on a rack that, together with all the other equipment on it, masses over 500 lbs. Isolating this entire mass from the floor would address the floor-borne, earth-borne vibrations while allowing the high mass of the TT (plus 400 lbs of additional mass) to provide the solidity it was designed to offer.
Being relatively poor, I opted for a poor man's well engineered solution: Sorbothane pucks. Before you snear (as I once did) consider that I was NOT placing these in contact with the TT or anywhere near it. I tried that for laughs using Vibrapods and it sounded dreadful. OTOH, placing Sorbothane pucks of a durometer and number appropriate to the mass being suspended beneath the 8 feet of the entire rack made a nice improvement. Backgrounds were blacker and low level details more audible with no detectable penalty in dynamics or bass response. A win!
As a bonus, isolating the equipment rack from the floor helped isolate all the other gear on it too. Fewer audibly obvious benefits for a CDP or amp than for a super-sensitive phono pickup, but certainly no harm.
So... keep your high mass TT as rigidly connected to whatever supports it as possible. Isolate from the floor, yes!, but do so as far away from the table as feasible. Isolation requires movement and movement saps dynamics.
My $.02.
I could not afford a Minus K, but I did want to isolate my 90 lb., unsuspended TT from floor-borne vibrations, particularly as the floor is suspended wood (though well built and sturdily framed). In trying relatively inexpesive solutions, one finding was consistent and clear: the closer the isolation element was to the cartridge/tonearm, the more deleterious side effects were audible.
High mass, unsuspended tables are rightly prized for their massive dynamics and good low frequency response. Light weight, springy tables simply can't compete in this area because movements of the cartridge and arm induced by groove modulations can actually wag the table. High mass tables resist this, but will be susceptible to floor-borne vibrations, including those from the earth itself, passing traffic, etc.
Placing isolation devices immediately below the table did lower the sound floor, as expected, but it also diminished dynamics and bass response. In effect, I'd converted my unsuspended table to a suspended (if massive) one.
What to do? Increase the suspended mass by moving the isolation devices from beneath the table to beneath the stand that supports the table. My TT sits on a rack that, together with all the other equipment on it, masses over 500 lbs. Isolating this entire mass from the floor would address the floor-borne, earth-borne vibrations while allowing the high mass of the TT (plus 400 lbs of additional mass) to provide the solidity it was designed to offer.
Being relatively poor, I opted for a poor man's well engineered solution: Sorbothane pucks. Before you snear (as I once did) consider that I was NOT placing these in contact with the TT or anywhere near it. I tried that for laughs using Vibrapods and it sounded dreadful. OTOH, placing Sorbothane pucks of a durometer and number appropriate to the mass being suspended beneath the 8 feet of the entire rack made a nice improvement. Backgrounds were blacker and low level details more audible with no detectable penalty in dynamics or bass response. A win!
As a bonus, isolating the equipment rack from the floor helped isolate all the other gear on it too. Fewer audibly obvious benefits for a CDP or amp than for a super-sensitive phono pickup, but certainly no harm.
So... keep your high mass TT as rigidly connected to whatever supports it as possible. Isolate from the floor, yes!, but do so as far away from the table as feasible. Isolation requires movement and movement saps dynamics.
My $.02.