Vinyl and subwoofers

cleeds,
Can't explain why others don't have the problem and I can't explain why others do. "Not plausible" does not rule out the possibility that the setup is screwy. That said, ok ok, I'll check it. :) Why is having the sub only 4 ft away from table a problem with concrete?
ct0517,
No stage had a filter. I have no doubt that a Krell is better...just wish I had the bucks.

BTW, the query "pumping woofer vinyl" resulted in over 100,000 results on Google.

golferboy

Why is having the sub only 4 ft away from table a problem with concrete?

The concrete has nothing to do with it. The close proximity between subwoofer and turntable suggests you may have some acoustic feedback between the two. That is only going to exacerbate any other problem you're having with setup.

I'm not familiar with your turntable. It's possible that it's just not well isolated. That may also be contributing to your problem.

golferboy

BTW, the query "pumping woofer vinyl" resulted in over 100,000 results on Google.

That is not at all surprising! There are more cheap turntables in the world than good ones. I'd wager more turntables suffer from improper setup than those that benefit from proper setup. As audiophiles, we're just a tiny percentage of those who listen to LPs.

It seems somewhat counter to logic to purchase a subwoofer that now requires a rumble filter.  If you can "hear" the subwoofer operating during normal playback, that typically indicates the level is set too high; turn it down a bit and see if that alleviates your intermittent problem.  Someone else mentioned this.  But as a matter of fact, 30 and more years ago good receivers and integrated amplifiers often did come with rumble filters.  They went away with the purist movement of the late 80s and 90s and possibly the realization that there was more profit to be had by not incorporating a rumble filter.  Do you perceive that the diaphragm of the subwoofer or your main speaker woofer is "pumping" when the problem is occurring?  In that case, and after you have exhausted the possibilities of re-arraging your components (see below), a rumble filter might help.

Your problem can also be due to placement of the components in your listening room.  Low frequencies can produce standing waves that contain quite a bit of energy which can induce physical movement of the tonearm/cantilever, generating spurious low frequency interference. Where is the tt with respect to the sub woof?  Try moving one or the other and see if that affects the problem you are trying to solve.  Someone else mentioned this, too.

Do you really know for sure that the sub woof is the culprit? Does the intermittent problem disappear when you disconnect the subwoof and run the main speakers full range?