Rippling cones

but it's not "inherent in LPs.

Not entirely true. Rule breaking by exception. While the vast majority do not flutter my cones, I have a small number of albums that make woofers and subs do that.

While recommending subsonic filters to get the new user a fix, it is definitely worth attempting a better mount with the springs. The Rega is likely too light to go directly on the springs but may benefit from a heavy intermediate support.

Great info. Thanks for the links to subsonic filters @noromance . Though I haven't had any problems lately but in the past I have had problems where my subwoofer(s) go into a frenzy. Though it appears to have been just one of them which was the closest to the TT. I assumed it to be airborne feedback from the sub through the cartridge which then looped back. IOW, feedback loop. The question then is whether the subsonic filter would take care of it. OR is this the same problemthat our OP is facing? 

@ hleeid , Thanks for the thread. Its a good topic.

@artemus_5 - tried moving the speakers away from the turntable.
Didn’t notice any change in the LS50s but looks like the larger drivers in the B&Ws seem a bit calmer.

@millercarbon So, I put the turntable on an old platform called ’’The Seismic Sink’’ I got from my uncle. The ’’Sink’’ is now on Audiocrast springs on the top of my equipment rack.

The room (15 x 19) is on the second floor with thick padded carpet over suspended wood floor.

Just noticed a weight imbalance among the 4 springs so will have to experiment with removing some of the individual springs from each spring unit.

Hopefully I can get around to getting things level soon and try again.

Also, my uncle gave me an old Vibraplane platform that weighs more than me! It has 3 air bladder type feet.

Is it worth the effort to get help muscling it up to replace the Seismic Sink?
I could then use the Sink under my Jolida tube integrated amp.

@noromance - have you tried either filter? quite the price difference!

I personally have used the KAB RF1 subsonic filter.  Solved my issue with rumble and even in a pretty expensive system (~60K retail), had no negative impact on sound.  I have not tried another option because this one worked very well