European Vibraplane?

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.

Looks like Newport is at the heart of those isolating platforms. They have their own technology:

http://search.newport.com/?q=*&x2=sku&q2=BT-2024

As I understand it's active: there is a mechanical level sensor, coupled to a valve which controls the airflow to each isolator:

http://search.newport.com/?x2=sku&q2=CM-225

The performance plots show a good 2.5Hz resonant point.
If it's available in EU for the price they show, it'd be very attractive.

Cheers,
bydlo

The "Drawings" tab explains it but should be probably viewed upside down.

A Newport engineer recommended these:

http://www.newport.com/SLM-Series-Compact-Air-Mount-without-Self-Leveling/139799/1033/info.aspx#tab_orderinfo

Very reasonably priced, but certainly not as efficient as the Vibraplane. They do have isolators with terrific vertical and horizontal isolation (1/1.5 Hz respectively), but the load required is just not practical for home audio application.

http://www.newport.com/S-2000-Stabilizer-Pneumatic-Isolators-with-Automa/844255/1033/info.aspx#tab_Overview

Then there is also this:

http://www.newport.com/BenchTop-Compact-Pneumatic-Vibration-Isolation-Pl/139761/1033/info.aspx#tab_orderinfo