European Vibraplane?

I have three 24"X20" Vibraplanes from SOS (Sounds of Silence). Two of the units are active (requiring a compressor) and one is passive (bicycle pump). I did try two used units found on Ebay for $350-500. THEY DID NOT WORK. I tried to use parts from both to make one functional, but in the end, it was just too frustrating. Repair estimate from Kinetic Systems was about $1,600 for each unit, so I went ahead and bought new units. The old style isolators and valves are no longer supported. The new units function perfectly.

One unit is under my 120 lb turntable and the other two units are under my SS amps. They each improved the sound, pretty dramatically. I was surprised at the improvement under my amps but was lucky to have borrowed a pair from a friend before I bought them.

I also had Steve from SOS order me from Kinetic Systems, two 135 lb steel ballast plates finished to match the VP units. These plates combined with the weight of my equipment approach the maximum design load for the units and thus they optimize the isolation.

Adding the steel ballast plates improved the performance of my components almost as much as adding the VP in the first place. These are very heavy units and extremely effective. They must be placed on a very sturdy platform, but the results and value are outstanding. They are much better than the Townshend Seismic Sinks. Details can be seen on my system page.

Thanks for this info, Peter.

Regarding Minus K, I have my TW sits on a platform on top of Minus K so aligning center of gravity on Minus K is a breeze even on unit like TW AC one where the motor stick out on one side. Regarding motion when moving tonearm, are you using your feet? Top platform on Minus K can move easily with enough force but seriously, moving a tonearm? May be if the whole turntable setup is 5 kg? I use a 100+ kg model as my TW+ Platform is just above 100kg. The amount of force to overcome the inertia is way way more than force require to move a tonearm. I certainly never notice any lateral movement on Minus K when I move tonearm in normal playing.

Never had a chance to compare to Vibraplane as it is not locally available and shipping from Europe or US would make it far more expensive than Minus K so that is not an option for me for now.

Syntax wrote,

"I also listened to Minus-K with the same turntable...good luck with that units. It starts moving even when you move the Tonearm to the first track. Even when someone would pay me for it, I would refuse to use it. They are ok for units with centered weight, but that's it."

The best isolation occurs when the motion is obtained with the greatest ease. It's a blessing and a curse. ;-) However, this might not be advantageous for turntables and even CD players that produce rotational forces. As I recall the Minus K negative stiffness machine used to be the Newport Corp Sub-Hertz Platform of yore and was modified for the audio market. Ooops, there's that name Newport again. I was under the impression that the rotational capability around the vertical axis of the Minus K had been disengaged but I might be mistaken. I also recall that the (Newport) Sub-Hertz Platform would go into its rolling swaying motion of 1/2 Hertz when a penny was placed on the top surface.