Vibraplane vs. Minus k for Turntables

About 10 years ago Stereophile had a good article on vibration control. It is well worth reading. It mentioned Newport Corp, which has a lot vibration control products, and I ended up using their air pods which have active isolation in both horizontal and vertical planes. I forget the f but it is on their website. By using their pods I was able to custom make my own rack where each shelf has active air isolation.

I did not like the Vibraplane because of the inconveniece its weight and that is uses rubber-like pucks for the horizontal plane.

Steve Klein of Sounds of Silence, who adapted the Vibraplane for audio, said he tried the next level Vibraplane which had a lower f (I think 1Hz) and said he could not hear a difference. But as stated above this would depend on your environmental factors.

No experience with the MinusK. Other than its size limitation it looks impressive. I'm sure all three companies have graphs showing the resonant frequencies and attenuation so one can compare performance.

I considered the Minus K unit as well as the Halcyonics. The Minus K is basically a well designed spring system. At it root the Vibraplane is also a spring system, in this case a bladder with a resonant frequency like any spring support. The Halcyonics in contrast is active with sensors and voice coils to counter the movements in the vertical and horizontal plains that its sensors sense.

I had what I thought was the best economical platform, the Neuance. I had six of them. I then tried the Acapella Silencio base which was much more authoritative in the bass in particular. I had a Vibraplane once but found the Mana Reference stand to be clearly superior. When I put the Neuance on the Mana that was clearly better. Then when I put the Acapella on that was a further improvement.

When I tried the Halcyonics under my cd player, I frankly thought I could not be hearing such an improvement. Although it was a pain to take it entirely out from under the cd player, a brief listening without it showed it was indeed making a greater difference than I had ever heard. Nothing in my experience even comes close.

What is the problem with the Halcyonics? It is too expensive! I don't know if the Minus K gets 50%, 70%, or even 90% of the Halcyonic. If I ever have a chance to compare the two I would welcome the opportunity. I suspect, however, that being a spring system, the Minus K would be nowhere near as effective.

The BM-8 gives vertical transmissibility values that are comparable to Halcyonics' benchtop product (the Micro) in the range >=5 Hz. However, the BM-8's horizontal isolation is significantly less effective than the Halcyonics product. As Tbg points out, there are significant differences between the Minus-k technology, which involves a resonant system, and an active electro-mechanical vibration-suppression system, such as that used by Halcyonics, Herzan, etc.

In most cases, laboratories opt for passive isolation over active. There are two main reasons for this: cost and complexity. Active systems have the edge in applications where settling time is critical - basically these systems behave like overdamped oscillators over a wide frequency band. A downside of active systems is that the cost is proportional to the number of degrees of freedom because of the number of transducers required. Also, feedback loops in such systems become complex; for example, small angular displacements of a payload can generate significant horizontal accelerations. Settling time shouldn't be much of an issue in analog playback as long as the resonant frequency of an isolator is well below that of the tonearm/cartridge combination. Also, for most audio applications, vertical isolation is likely to be much more important than horizontal.

Ten months ago I looked into the Vibraplane, Minus K, and the Halcyonics platforms. The Minus K web site, namely the links to the audio applications, prompted me to lean toward Minus K. It is made in America, utilizes only passive components that won't hold you hostage to a foreign manufacturer to keep your device working.

I began my turntable project needing a 350 lb isolation device. It rose up to more than 600 lbs. My Minus 650 BM 1 will be here in about a week. I've never seen one but the help I received from the folks at Minus K prompted me to opt for their product.

The Library of congress uses them along with Simon York tables for archiving. They looked into the Halcyonics units but chose the Minus K. Keep in mind that they don't have acoustic feedback problems at the Library Of Congress, monitoring is probably done with headphones.

All that said, I don't anticipate problems with horizontal oscillations with a 650 lb table spiked to a concrete floor. The Minus K should have vertical isolation equal to the Halcyonics.

Vibraplane, I checked them out when I saw, "the table only," on Audiogon for $2200, that was a year or so ago.

I found the company that manufactures, and private labels the Vibraplane, and received a quote from the industrial distributor of the product, $1500 without the pump. If you feel that a Vibraplane is your ticket, Google it and save some money.

I'll post after I have it up and running and confess if I've spent my money unwisely.

Ken

.
Ken,
.
Thanks for sharing your thought process in deciding to get the Minus k. I am leaning towards getting the Minus KWS-3M Vibration Isolation Workstation for my upcoming 220 lb Teres Table. The work station sits at 29 inches high and solves my problem of what stand to use with the Minus k.
.
Did you ever consider get the work station or have any conversations with the Minus K people about using a workstation? What type of stand are you planning on using under the Minus k ?
.
Do know if the Minus k products have any provision for leveling ?
.
Regards,
Larry
.