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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
miner42 OP
709 posts
 
Listening room is on a second floor; suspended floor.  Main floor is a concrete slab.  I have done the dance thing around my TT and no problem with noise coming through speakers.  If I yell/scream into my cartridge I do hear a sound through the speakers.  As mentioned, I have now relocated my speakers to the adjacent walls and the REL to the adjacent wall, too.  REL is approx. 16.5' from TT; nearest speaker is 5' from TT.  I can play with monitor only with no issue but once I introduce the REL I need to turn gain down to reduce feedback as volume is increased.  Crossover is set at 49Hz on REL with 180° phase.
miner42 OP
709 posts
 
...and I did remove my KAB RF-1 filter and noticed the music is much more 'cleaner'; that filtered appeared to be adding noise to the music.  Downside is the woofer pumping is back during TT usage.  I will have to monitor the gain and find a happy medium.
raymonda
855 posts
 
Well, as I suggested early on, the best way to minimize your feedback problem was to relocate your table.

Whatever you do, don't put your table in the corner. That too can cause issues.

raymonda
855 posts
 
Often times when you have feedback issues it can be a combination of both mechanical and air born problems. Keep fighting and refining solution to both and I think you will eventually solve your problem.
slaw's avatar
slaw
20,546 posts
 
handymann,

Yes, room treatments do wonders in providing excellent bass response while also taming bass room nodes.

toddveronne,

Sorry. I guess the lack of the OP responding got my juices flowing..

Your thanks to the OP, while relevant, are ultimately misplaced. The thanks for the gain you've achieved through the OP's posting should go to all who have provided the info.

Your use of three springs, "too wobbly when I tested it". What/how did this translate into the sound???

miner42,

You never responded as to your "audio console". When I read that term, I envision an enclosed structure? Given all of the problems you need to overcome, IMO, having an enclosed audio console in the center of your speakers on a second floor is quite a lot to overcome? I do realize it's not relevant now?

Given the changes you've made, I'd say it's time for some quality bass control. I've had great success with the Vicoustic Extreme Bass Panels.

"Woofer pumping during tt usage", again a sign of the tt isolation being ineffective.

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