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Need help solving a system problem

The equipment:

Martin Logam ethos
musical fidelity m6si integrated
musical fidelity nu vista vinyl phono pre
EAT C Sharp TT with a Kiseki Purple heart cart.

The issue simply put:  when I rest the needle on the record (record not playing) and I turn the volume up to the 12 o'clock position, I get an incredible amount of woofer vibration from the logans.  Same issue when playing a record. 

I've tried:
1.  better isolation ...keep in mind record is not playing so acoustic feed back is out of question.
2.  Speakers are 43 inches from the needle when on record from each side.  tried moving to max distance room will allow to no avail. prob still occurred
3.  tried a different table with different cart.  got same issue.
4.  Upgraded stand ...isolation again.
5.  tried different tonearm cables, different inputs on pre...same prob.

Any ideas are welcome.  I love my system just cant play it loud....and sometimes I like it loud.
polkalover
cleeds
2,065 posts
 
tablejockey
ALL system's speakers will do the same with a table.
Not so. Feedback may be a common problem with turntables, but it is not inherent in all systems. My speakers are flat, in room, to below 20 hz. I have no feedback at any volume level, and my turntable sits remarkably close to one of the woofer columns. It's all about isolation and, imo, mass. 
stereo5's avatar
stereo5
2,766 posts
 
The KAB Rumble Filter uses all audiophile approved parts.  I run mine via the tape loop on my preamp and I hear no difference with it engaged or not, but it certainly stops all the woofer pumping.
williewonka
1,826 posts
 
@polkalover - What kind of woofer vibration?...
- does it pulse evenly? e,g, at a partucular frequency (which freq)
- is it spiradic? e.g. only happens when you walk around it
- are all the pulses of equal amplitude or do they vary?

Since this only occurs when the needle is placed on the record and if the pulsing is of a constant frequency and amplitude then it sounds like a resonance issue.

Have you tried varying the bass control knob on the rear of the speaker? Does it make any difference ?
- try one turned up fullty and the other turned down

Have you tried moving the speakers slightly (e.g. 1"-2") further in/out from the audio stand. The resonance may be occuring between the speakers and the cartridge is picking it up.

Maybe it's a standing wave issue?

Just aome thoughts - Steve


polkalover OP
14 posts
 
Just wanted to thank everyone for their input.  Here's an update:. I purchased Harrison labs 30Hz high pass plugs and although it allows me to play it a little louder the rumble still occurs at about the 2 o'clock position.  Once again not playing a record just resting needle on record.  So this leaves me with 2 options: 1. Spend some more scratch for the KAV rumble filter and see if that solves it or 2.  Sorbothane isolation feet for table.  Room reconfig. Is not possible..... additional thoughts, ideas are welcome
cleeds
2,065 posts
 
polkalover
... rumble still occurs at about the 2 o'clock position. Once again not playing a record just resting needle on record ...
If you hear noise without the platter spinning, then its source is something other than rumble, and is probably feedback.
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