Feedback through turntable


My system consists of a McIntosh C2300 preamp, MC452 amp, MCD500 SACD player, VPI Aries 3D with Ortofon Cadenza MC cartridge, Manley ChinookSE phono stage, PS Audio P5, Sonus faber Cremona Auditor M speakers and REL B1 Sub bass system.  My issue is with turntable use only; SACD has no issues.  On my pre when volume is +55 (peak at 45watts) I start to get feedback through the turntable - a sort of low freq sound, back off volume and it goes away.  My Auditor M speaker is about 3 ft away and in front of turntable.  I do have a rumble filter (KAB) installed between preamp and phonostage to help with sub woofer pumping.  Due to room layout I cannot rearrange the setup/move turntable.  My turntable is on a 2.5" block of wood and that sits on 4 isolation blocks via spiked feet.  Any thoughts how I can eliminate this problem?  Harry Weisfeld with VPI states he has 4 15" woofers (JBL Everest) near his Prime Signature setup with no issues at all.  Why am I having this problem and how can I eliminate it?  Thank you in advance for all feedback.
miner42
@toddverrone,

I cannot think of ANY area of isolation in my 30 + decades in audio where rubber (innertube) doesn't degrade the joy of listening!

Forget about the idea of the whether maple or teak is the culprit. It is the RUBBER!

Happy listening!
I wanted to tell miner42 that, while he had the upgraded feet for his tt, that in it's center is rubber! That is what connects, (forget that)  Traps! the resonances by not allowing a freeflow of these vibrations!

Rubber is not your friend!

This is certainly not his main concern. It is, a valid point.

There, I said it.
"in my 30 + decades in audio".

Slaw, you are the audio Rock of Ages. What was your system like before the discovery of electricity?  ;>) Kidding!

Dave
Totem395 2-21-2017
Does the the issue arise even when not using the sub?
Miner42, I don't think this question has been answered.  Also, where is the sub located relative to the turntable and relative to nearby walls, and what is its rolloff frequency set to?

Regards,
-- Al
 

Good stuff Slaw. I want to get rid of the last of the rubber in my system, the inner tubes in the original Seismic platforms. I have been planning on getting some of Geoffs springs, and perhaps some of the current Townshend Seismic Pods. I find the Pods more than a little overpriced, but what else is new?!

I too had a VPI HW-19, and considered it about as good as a suspended-subchassis design could go. But you're right---that MDF platform was it's weakness. I never heard the later acrylic version, having moved on to the Townshend Rock table, which certainly doesn't have THAT problem!