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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
Ag insider logo xs@2x
cleeds
5,950 posts
 
polkalover
.. 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.
The turntable doesn’t have to be spinning to generate acoustic feedback, which is what it sounds like you have here.

folkfreak's avatar
folkfreak
1,349 posts
 
This is acoustic feedback. Just because the frequency is too low for you to hear doesn’t make it not feedback. The trigger could be your footfalls or environmental sounds but that can be enough to set it off.

The simple solution is a rumble filter which will cure it for sure. Otherwise you need much more sophisticated isolation. You did not say how far you can get the table away. I’d say a minimum of ten feet and ideally more. If you are six feet or less then you are making the problem harder to fix. Real isolation solutions for subsonic frequencies are very expensive (think thousands of $) - space and air is much cheaper!


tablejockey
3,902 posts
 
A situation, if you didn't notice  the woofers, that isnt going to harm anything.

ALL system's speakers will do the  same with a table. 

Lookup subsonic concerns.
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