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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
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.
rodman99999
3,557 posts
 
Is your’s a Purpleheart or a Purpleheart Sapphire? Their compliances differ, dramatically. https://www.vinylengine.com/cartridge_database.php?m=Kiseki&mod=Purple&t=any&sort=2&...= Given the effective mass(16.5 Gr) of your arm, weight of the cart(7.5 Gr) and the resultant(anticipated) resonances, you can expect less than great results, with either cart. They fall to either higher or lower of the typically desired/recommended range(13 & 7 Hz, respectively). https://www.vinylengine.com/cartridge_resonance_evaluator.php?eff_mass=16.5&submit=Submit  If yours is the Purple, you might try adding some mass to the tonearm.
polkalover OP
14 posts
 
@rodman99999 
So based on this chart there's a compatibility issue which raises this question...see link https://positive-feedback.com/reviews/hardware-reviews/eat-c-sharp-turntable/

He had my TT set up and had great results.  I'm not thoroughly convinced that is the issue, but makes a case for the problem.
rodman99999
3,557 posts
 
That reviewer may have had a subsonic filter(many phono stages do), speakers without very low extension, a room with differing Sabine coefficients, etc. They don’t mention anything, regarding their reference system. It would be simple, to experiment with your tonearm mass/cartridge weight, to see if anything changes. Also, very advantageous to determine at what freq your system(both great pieces, btw) is resonating.
rodman99999
3,557 posts
 
Just curious: At what level do you have the Bass Control set, on your Logans and- does your phono stage's IEC button, make any difference when engaged?
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