Same problem on 3 different Turntables. As a last resort, I bought a KAB rumble filter which I run via the tape loop. I do not notice any less bass and my system really swings. The filter even uses audiophile parts in it. New it was 179.00 but I saw one on here a couple of weeks ago for around 100.00 That, is a good deal. Regardless at what others will tell you, in my system it did not cut the quality of the bass or the deep bass. I can rattle the windows playing vinyl if I want. The sun has absolutely nothing to do with it.
Why are my woofers pumping?
The other day, with sunlight direct from the side, I noticed that the
woofers in my speakers are pumping in and out, much more than I was aware of,
when the stylus is in the groove, even between tracks (no music). I can see it, even if I don’t hear it. Why
does it happen? The woofers behave normally (no pumping) with digital music, and
when the stylus it lifted from the groove, so it is not the speakers, amps,
preamp or phono stage.
I’ve read that the typical reason for woofer pumping is that the cartridge / arm resonance is too low. I tested, with my Hifi News test record, and yes, the lateral test puts the resonance at 7 hz or so – too low (but I’ve seen some doubts about the results from that test record). It is strange, since the combo I use – Lyra Atlas cartridge and SME V arm (on a Hanss T-30 player) is supposed to work well. I tried to strip my arm of extras, cleaned the damping trough, etc – but it did not help much.
Anyone has an idea, why it happens, or what to do about it?