Woofer pumping WHY??

I have a B3, essentially the sames box, but you have the 12" woofer.
When I see my B3 looking like the woofer is going to jump out of the cabinet, usually means 1-system is cranked and the particular recording is "hot" on the low end, so gain needs to be turned down. I don't keep my sub at one supposedly "perfect" level. While it can be left alone for casual listening and not cranked, ALL recordings are different, so I adjust accordingly. I think REL got it right with the remote for the Gibraltor series.
The second is the actual record.iIf it isn't perfectly flat, when cranked, the movement of the arm over the warp is going thru the cart.
After countless sessions over the years, my REL permanently resides behind the listening position, about equidistant to the floorstnders.
All setups , rooms are different so my experience may not even apply in your setup.
Incidentally, my REL is on Mapleshade brass/slab which I've found not only a nice looking, but sonic tweak. Consider it, if you haven't already.
My floor stander have the same setup.

Ok I'm connecting the sub with the Spkon cable and all three leads to the back of the amp, Otherwise wont the amp then SEE the REL in the system? Before I got the new table I had been using the REL for quite a while with no problems ever. The REL is plugged in to the wall using a 3 prong cable (both the spkon and power cord are from Signal Cable). I do see the woofer pumping on the main speakers too, and this seems to occur more toward the outside of records im playing. The Sound is very very good. If that says anything. But this cone movement needs to be addressed. I'll do a little more troubleshooting and get back soon. Do a lot of vinyl spinners use outer rings?? I see that most of the HIGHLY re guarded phono preamps Don't have subsonic filters? Like my MS Phonomena. I don't think my phono stage is the problem. I respect every ones input thank you. Stereo5 you sound like my older brother..LOL that's what he keeps telling me. He has a KAB. Yogi, Wouldn't the sound be bad or unpleasant with a bad arm/cart combo? because the sound seems to be gorgeous! Al, Im using unbalanced cables to amplifier and my speaker cables are spades, the REL Spkon cable is Bannanas on amp side. I have a concrete floor with carpet. Salamander rack with Mega spikes. Yogiboy, I think is on to something, but the sound is so dam good? So I am perplexed.

Mattmiller,I standby that the cartridge arm combo is not a
good combination,and will wreak havoc. The sound is good
because the problem is in the subsonic region that you will
not hear. If you don't address this you will have the problem till
the cows come home. You should get the filter if you think
that will work and return it if it does not fix the problem. BTW,if
the NeedleDoctor tells you there is not a problem then he
should go back to med school ! You should get a test record
with the resonant frequency test. I use the Shure TTR 115
ERA lV,you can find them on Ebay for about $20 bucks. The
other fix is to get a higher compliance cartridge or an arm with
more mass.

Yogiboy , no doubt you are correct,used to see it all the time back in the day with heavy arms and HIGH-compliance carts.
Do you,or anyone else, have recommends for higher compliance MM carts readily available ?

Schubert, Ortofon,Grado,and some Soundsmiths all have medium compliance and will work with a tonearm that is from light to medium. I don't think they make super high compliance cartridges and super low mass arms that was the fashion many moons ago. I was kind of surprised that the arm the OP has was only a low 8.5 grams mated with a cartridge with a low compliance