2. analog
  3. 1359750279

HRS M3X isolation base or Minus-K?

Hi All,

I'm looking for some input about these two platforms under a non-suspended turntable. Anyone have experience with both?

I have a Brinkmann Oasis on the way, for which HRS makes a custom platform. I could buy a Minus-K MB100-8 at roughly the same cost.

Minus-Ks are a known quantity to me because I've used them under two non-suspended decks with great results. I have no experience with the M3X. Either platform will sit on an Adona rack, spiked to a concrete floor.

Minus-K does a great job of isolating from external resonance, especially in the vertical plane, but does nothing for self-noise from the turntable. I found that an additional shelf is needed between the turntable and top-plate of the Minus-K, both to damp this source of resonance and to add enough weight to reach the upper range-limit of the suspension for best performance. An Adona multi-element shelf (granite bonded to MDF) resting upon Vibrapods works very well. (Vibrapods, believe it or not, were better than anything else I tried, including myriad combinations of sorbothane disks, Herbie's Big Fat Dots, etc.)

My sense is that the multiple damping layers of the HRS would address this self-noise better than the Minus-K in combination with an Adona shelf and Vibrapods, but I'm not sure. On the other hand, the HRS almost certainly will not be as effective against external resonance as the Minus-K.

I'm kind of tempted to go with the HRS because Brinkmann recommends it, and because HRS told me in an email, "We know the Oasis table very well. Our custom designs...are based on direct experience with this turntable. Our chief engineer is currently using this table as one of his test turntables."

It's a conundrum.

I welcome any suggestions but I'm especially interested in direct experience comparing these two platforms.

Thanks,
Bill
wrm57
wrm57 OP
1,054 posts
 
Rsf507, I know Vibraplanes are a great option. I'm a bit put off by the idea of bladders and compressed air, probably because I had an irritating time with a leaky seismic sink long ago. No comparison between the two products, I know, but still.

Geoffkait, That's a good point about the importance of low frequency structural isolation. Minus-K reduces to 0.5 Hz vertically, much lower than HRS, which I think is 5 Hz.
sksos1
388 posts
 
Wrm I understand your hesitation regarding air bladders but with over 6000 units sold and many now over 25 years old and all still working as designed, there have been less than a handfull that an isolator required replacing and almost all due to sliding the units. My own units have worked flawlessly for 26 years, yes I needed a new pump but we have since changed pump manufacturers.
To note there are 6 air chambers and 3 have bladders but the Vibraplane also uses a slip plate technology (which is why it requires mass and weighs the 150 pounds) to get isolation in both the vertical and horizontal planes.

Dealer disclaimer
wrm57 OP
1,054 posts
 
Sksos1, I hear your pitch.
actusreus
733 posts
 
Wrm57,
Forget the Vibraplane or the HRS platform; go with the Mapleshade Vibration Control System (brass footers, maple block, and Isoblocks). I quote from the Mapleshade catalog: "In independent head-to-head listening tests, the Mapleshade [VCS] invariably sounds better than $5000 Vibraplane air suspension platforms-much warmer, more detailed, and more naturally dynamic at less than 1/20 the cost. Ditto for expensive composite platforms, sandboxes, and air tube/bladder suspensions from Symposium, Ginko, HRS, Seismic Sink, Bright Star, Nuance, Sistrum, and Silent Running."

I jest of course.
peterayer
1,382 posts
 
Brinkman was showing two of its turntables on Vibraplanes at the latest show in NYC. The sound was fantastic.

I tried the mapleshade Vibration Control System, then a Townshend Seismic Sink and now use an active Vibraplane. There is just no comparison. I did have custom steel ballast plates made to preload the Vibraplane so that with the turntable and amps, the total supported weight is close to the maximum design load. Excellent results.
More to discover