Woofers getting workout, but no bass


I'm puzzled: I'm noticing just about every LP I've played in the past couple days has my 10" woofers moving like mad, but not in time with the music and regardless of whether there's any audible bass.

I can only conclude that I have subsonic frequencies occuring (my phono stage doesn't have a filter). What would cause this?

Relevant components:
Speakers: Wilson Sophia 2's
Turtable: TW Acustic Raven One
Phono stage: Tron Seven

Thanks in advance.
madfloyd
mapman, I experienced the same problem a while back and purchased rumble filters. It took care of some of the problem but not all. In my paticular case a change of cartridge did the trick- no rumble woofer movement now. I know this is not what you want to hear and may not be your issue but it is what it is. I will offer to let you try my filters to see if they work for you if you like- no charge of coarse. PM me with your address if you want to try them.
YEs, changing cartridges may have an effect but I am not certain how to determine what to switch to to assure desired results. Higher compliance maybe? Something that produces a different resonant frequency with the specific tonearm utilized perhaps?

PErsonally, I am not a fan of filters of any type. With proper setup and match of equipment, the problem is usually not an audible issue to start with. GEtting to that is the trick of course though. Record players can be tricky beasts and not easy to get right!
One thing you might try is to put a gram or two of something like blu-tack on your headshell and a corresponding amount on the counterweight so that your VTF remains the same.

This will change the effective mass of your arm and the resonate frequency of the arm cartridge.

It may or may not work but it is cheap and simple to try.

Regards,
Todd
Here's more background info on cartridge compliance, resonance frequency, and potential impact for rumble, etc.

http://www.gcaudio.com/resources/howtos/tonearmcartridge.html

Hope this helps.