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

Showing 3 responses by geoffkait

I think you will find that isolating the component from low frequency structural vibration is considerably more important than damping or offloading internal vibrations of the component in terms of sonic results. And it's much more difficult to reduce vibrations with frequencies on the 0-5 Hz range than it is to reduce vibrations produced by the component that are farther up in frequency. So, go with the platform that has the lowest resonant frequency and the most directions of motion.
Pierre has one thing even better than some high-fallutin' engineering degree or engineering background - good ears! I'm especially fond of his idea of suspending all cords and cables from the ceiling using thread with a little rubber band on the ceiling end to hold the thread .
Sbrown wrote,

"The guy with just the bases added subs to his system last year. For logistical reasons, he had to place his tube amp on top of one of the subs. He stuck the SRA between the amp and sub and has never had an issue."

I think I probably would have tried to come up with a little bit better location. He never had an issue that he was aware of, anyway.