Woofers getting workout, but no bass

you are experiencing a very typical phenomenon as Vegasears suggests. Only a filter that eliminates those lower frequencies will eliminate this. I would venture to say that the other possible causes mentioned may play a diminuative role also. Seek out an inexpensive filter online and try it out for you to see. Then, after concluding that this may be the case, you can start getting the typical audiophile paranoia of whether this is now altering the overall signature of the music.

Rumble filter
http://www.kabusa.com/rf1.htm

Thanks for all your replies. I do think it's worse at the beginning of an LP.

My floor is concrete, but the turntable is at the back of the room where there is bass buildup. I think my stand is fairly solid, and I'm using a Terrastone platform underneath my turntable. Coincidentally, I just received this yesterday - it replaced a wooden shelf. I can tap on the terrastone shelf fairly hard and there is (seemingly) no effect on the turntable. I had the rumble issue before changing the shelf.

Dlcockrum, I have the TTWeights peripheral ring, I'll try that and see what happens.

I have to imagine this is adversely affecting the sound of LP playback...

Tried the TTWeights peripheral ring and it didn't help.

I'd be pretty bummed if I have to replace my cartridge.

YEah, its rumble originating from the warp inherent in many records that is typically at highest magnitude at the beginning of the side/outer edge perhaps magnified by sonic feedback from vibrations.

A concrete floor is good. IS the table sitting on a solid foundation/stand upon the floor? If not, it should be. If it is sitting up high on a stand, try a lower platform perhaps?

If the table is sitting rock solid and you still have problems, a switchable subsonic fileter may be the only remedy, but if all else is well, then in most cases practically this is not needed.

If your woofers are moving with large excursions for reasons other than the signal from the record, then this is utilizing power to produce noise and the power is not then available for the actual signal/music.

BTW, some of this (woofer excursion due to rumble) is naturally inherent in record playback. If you have everything else set up well together and the records are not abnormally warped, then I would not worry about it.

Not familiar with your table, but another thing that can help is to have a tt platter that is large enough in diameter to support the record all the way to the outer rim properly. TAbles with smaller platters are generally more susceptible to this particular curse.

Also, if you have a dustcover, keep it down while playing. THat should help minimize the unwanted effect.