Turntables currently considered top of the range. Do you know what they are ?

I’m a little surprised that Acoustic Signature did not make it onto the conversation. Many good options if tables and arms from this company. I have there Hurricane with two arms. The TA5000 9 inch and TA2000 12 inch. Running Hana Red and Dynavector TKR. Good value in my opinion. 

The Minus-K is extremely impressive because it has such a ridiculously low resonant frequency - like 0.5 Hz or less in one of the directions. So it's truly effective at full-range isolation. Watch some videos of it in action; it's like magic. A really good, well-tuned spring suspension is a little higher in resonant frequency, but still very effective. Squishy feet / layers are much less effective at isolating lower bass frequencies, but still have some positive effect here. I think harder layers and platforms are really only effective at the midrange and up - no doubt, there is much good to be done here, but it's limited in range. Adding mass can help but it needs to be added in the right place in the right way, and with enough rigidity to suport it - yada yada. You could actually make things worse in some cases by carelessly adding mass (e.g. heavy turntable atop a cheap tower rack).

Anyways - yeah, the Minus-K "negative stiffness" tech looks super impressive and is on my bucket list to try some day :) 

I suppose you could say guys like me with an expensive deck (Master Innovation) and no Minus-K have the audiophile equivalent of a "kick me" sign on our backs lol. I have my Master on a CMS Maxxum rack which is no joke - but still, I think a Minus-K would be best. The SOTAs are simply life on "easy mode" by comparison. Especially the Csomos, which has extra mass in its subchassis. Just really super chill and immune to all the nonsense happening around it (caused by me!).

@mulveling yeah, I've been thinking that if I go through with that Master Innovation upgrade I should really include the Minus-K in my budget. If the windfall I expect affords me the Master it will afford the Minus-K as well. :)

Minus K requires a few specs to get started… center of mass, total mass and envelope dimensions..mostly the feet touch points… about $5 K for the Kuzma i spoke about… would be similar for my Bardo. Think aerospace lab optical / laser bench vibration isolation = minus K

@tomic601 It seems Minus-K have already worked out the correct product for the Clearaudio Master Innovation. It’s the BM-8 and they show an example of one with a Master Innovation on it. It looks like the cost for one is $3,635.00. That’s about the same cost as the HRS M3X2 isolation base. They show that on this page: https://www.minusk.com/content/applications_vibration_isolation_systems/audio_reproduction_turntables_vibration_isolation_platforms.html