VPI Rim Drive vibrations

It would be interesting experimenting using the Classic aluminum platter. Not sue if it’s compatible with the HRX? For sure the HRX Rim Drive will have an easier effort and less stress pushing the Classic platter than the heavy Super Platter with two acrylic discs sandwiching the aluminum disc in the middle.

In theory the pure aluminum Classic will induce vibration ringing compared to the Super Platter with damping on both end using acrylic. It’s an interesting point I like to share with everyone in this thread as you all help me so much.

When I first install the TerraCones on both the HRX motor drive and the HRX turntable footers, the touch point of the Rim belt was touching the top acrylic disc on the Super Platter. You can get away with 33 rpm but at 45 rpm you begin to hear a weezing spinning sound on the LPs. I think the acrylic is not perfectly uniform like the middle aluminum disc.

With the added adjustability of the brass cones underneath the TerraCones footers, I reposition the Super Platter where the Rim belt is touching the aluminum middle disc where its manufactured more evenly like the Classic platter. The weezing spinning noise disappeared like Houdini. The experiment suggests that always use the Rim drive on the aluminum disc of the Super Platter. If there is any minute noise, let the acrylic absorb it like the original design intention.

The TerraCones also enables me to perfectly level the Rim top plate with the Super Platter. To play with Rim driving the platter, it must be perfectly level on both spinning disc. My Clearaudio Bubble is centered perfectly on all surfaces of the turntable, Super Platter and Rim motor drive. The fine-tuning is necessary for best results.

Some of you may recall the esteem editor Myles Astor from his past Ultimate Audio magazine, recommends using Walker Audio damping discs on the HRX. I have four large Walker disc on the corners of the HRX Rim motor drive and two on each side of the tonearm base support on the HRX turntable. The fun is tweaking and hearing the improvement. Needless to say my Graham Supreme pivot tonearm is rock steady and doing the Graham magic. The Walker discs made perfect sound imaging and cleans things up. The Walker will eat up any spurious vibration.

I am still dreaming of a slightly larger heavier top plate on the Rim Flywheel to push the heavy turntable platter with better compatibility. I think VPI maybe doing something, but no announcement.

Thanks again.

it was a revelation when i sold the Superplatter and installed the Classic platter...much better in every way. The Superplatter sounds tubby, closed in, and restrictive compared to the Classic.

Yes, I totally agree Stringreen!

Wasn't there an issue with the Superplatters being out of round? Which could raise havoc when one is combined with a VPI rim drive. Perhaps that was much of the OP's problem. Personally, I think both the plinth and the external rim drive system (any rim drive system, not just VPI's) should be firmly joined together and very rigid, no movement at all between one and the other should be permitted. Further, the rim drive apparatus should be very massive. (Let's not forget Newton's Third Law of Motion; the rim drive torque promotes a tendency for itself to rotate opposite to the rotation of the platter.) But that's just me.

I agree Lewn....and Harry agreed with me as I was going through this issue with him, that the Superplatter isn't and I was told just can't be made with the tolerances needed to work with the rim drive....that's one of the big (maybe the biggest) reason the Classic platter was/is manufactured. By solidly anchoring the platter and its ancillaries to my very solidly supported table via the BearPaws, and allowing the errors of the non-round platter to be accommodated with the sprung support of the motor assembly, I was able to eliminate the rocking of my then 10.5i. That rocking was making me nuts to look at it in operation..surprisinglyl not heard to that great extent in the listening. The motor assembly would dance in time with the non-roundeness, but that didn't bother me as much. However, I wouldn't rest until I found my fix.