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
The Wikipedia seems to indicate that rumble affects the sound even when not audible.

"Even when not audible, rumble can cause intermodulation, modulating the amplitude of other frequencies. The ‘unweighted’ response curve is intended for use in assessing the level of inaudible rumble with such intermodulation in mind"

Also, one has to wonder how a speaker can produce accurate bass when the woofers are pumping violently.

That being said, I've given up on doing anything about it for the time being.
I just look at mine when they do it...and it hypnotizes me. INTO WANTING MORE EQUIPMENT!!
"11-01-09: Vandermeulen
I just look at mine when they do it...and it hypnotizes me. INTO WANTING MORE EQUIPMENT!!"

Want more equipment?
Try a subsonic filter

Bob

Definitely, you are reproducing the record warps. You need a subsonic filter. Your amps are using a lot of power to reproduce frequencies that you cannot hear, and that you don't WANT to hear. Also, if you are using a heavy arm with a high-compliance cartridge, this makes the problem even worse.

Tell us what cartridge and arm you are using together.
Oh, I just found your answer. The Triplanar/Dynavector XV-1s is a fine combination. So you simply have warped records and a system that reproduces 3 to 10 HZ very accurately. You need to insert a subsonic filer.

Sounds that you can hear, you cannot see. If you see your woofers moving, it means you are reproducing frequencies that should be filtered out.