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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
williewonka
3,075 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
115 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
Ag insider logo xs@2x
cleeds
5,948 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
6,131 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
115 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.
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