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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
mijostyn's avatar
mijostyn
8,570 posts
 
Woops Wrong test LP. This one  https://www.amazon.com/HIFI-NEWS-Test-Producers-Cut/dp/B00KMCL1PE
jjss49's avatar
jjss49
6,612 posts
 
another option is get a phono stage with an effective subsonic filter - higher lehmanns have that feature for example

but other advice is spot on... best to find the source of rumble, but it may be coming from the TT/cart itself coupled with records
lewm
13,633 posts
 
Not that I think it’s relevant to your immediate problem, but increasing the weight of your counterweight actually has the paradoxical effect of reducing the effective mass of your tone arm, because effective mass is affected by the square of the distance between the pivot and the center of mass of the counterweight. Therefore, when you went from 140 g to 180 g, you then moved The counterweight closer to the pivot to reset VTF. Thus you reduced the quantity that is squared in the calculation. You actually would be better off to use a slightly lighter weight counterweight and move it further away from the pivot. If you want to increase effective mass.

As to your immediate problem, absent undetected and unknown problems with your equipment that none of us are privy to, I suggest you need to move your turntable to another spot in your listening room, and see if that helps. Putting it on the floor like Miller carbon suggested is also a reasonable idea, but put it on the floor in another part of your room, if you can.
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slaw's avatar
slaw
23,108 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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