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Sub Sonics and woofer pumping

I have a VPI prime on bear claws sitting on a maple base. Floor is concrete. I use a Nagaoka MP500 cart with going to an ARC PH3se phono pre, then to a Herron 1A preamp. Amp is an ARC Classic 60. Speakers are Thiel CS 2.4’s. 
I get pretty aggressive woofer pumping with vinyl. 
I’ve lubed my bearings on the table.

my alignment is spot on. 
Tracking force at the upper limits of cart. 
I’ve added the 2nd pivot point to the 3D arm. 
I’ve even switched out the counter wt to a much heavier unit and added a comparable head shell weight to change the total mass of arm. To no avail. 
None of these things have had any effect in reducing the pumping. 
I REALLY don’t want to use a rumble filter. 
I’m left with the conclusion that the cart may not be a match for the arm, even after adding all the extra mass. 

Any thoughts or solutions. 
last_lemming

Showing 2 responses by slaw

slaw's avatar
slaw
22,816 posts
 
Also, make sure your two VTA tower screws are tight.
slaw's avatar
slaw
22,816 posts
 
Curious as to why and when you changed to BearPaws and what difference you noticed?

Never said what TT support/rack you’re using,?

Just looked at your system page. Here’s my assessment:

I know we have to deal with our own environment but having a tt in the corner/behind a speaker is probably THE worst placement for a tt, especially on a high rack.

I have an inexpensive solution for you, get one more maple shelf just like you now have under your tt and place four appropriate load rated springs between the two maple shelves. If you have access to a drill press, recess the springs 1/8" into the upper & lower shelves. This step isn’t necessary but advised. Thank me later.

Look at my system page.
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