Subsonic Rumble Solutions

..have you tried removing the squishy balls and tried the table solidly in place? ( Squishy balls never worked in my system) Also, a few years ago, if I had the grill cloths off, I could see the woofers slowly advance and contract rhythmically (probably not your issue) When I went to an all balanced system, the problem went away.

Squishy balls didn't help. However, the balanced idea has merit, my new phono stage has balanced output so this may be a possibility.

DS

I have bass cone movements every 30 seconds lasting for a few seconds. It is not really subsonic, but I think related to this topic anyway.
It is constant and audible with or without music playing but it only happens on the phono stage, not on the other inputs.

I have a Lyra Skala connected to a Lyra Erodion stepup and then an Audio Note M5 Phono.
The earthing is connected from the cartridge to the stepup and then continues to the AN M5 Phono.

The preamp sounds wonderful, but when the cone movements occur, it blends with the music resulting in clearly audible distorsion.

Do you have any idea what it may be or what I can do?

Nice thread. I stumbled upon it by accident. I'm posting since the last post is from April this year so I figure it's ok to keep it alive.

I'm with the camp that rumble/flutter/woofer pumping is part of the vinyl experience. If you don't experience it, then count yourself lucky. My setup is fine on paper but on certain records the woofer pumping was insane. It didn't seem to have much to do with record warps.

I think whether anything in the signal path causes a deterioration in transparency or affects sound quality is a moot point if your system is experiencing a rumble problem despite attempted mechanical fixes. The woofer pumping will have a much worse effect on the sound than a good quality filter that will relieve the amp from trying to reproduce LF signals that are not audible, and the woofers from unnecessary and stressful movement that with time will most likely cause damage. To me it's a silly argument to make. We're not talking theory, but practice; you're not listening on paper but with your ears and observe with your eyes.

For those who want a ready solution: get a KAB rumble filter. I got one, I'm in vinyl nirvana every time I listen to records, no woofer pumping, no distortion, no audible sound compromise; in fact, the sound has improved.

My rumble went away when I decided to change out my cartridge, which on paper looked to be a great fit with on resonance issues. I went from a Dynavector XX-1 HO to a Transfiguration Temper LO. I didn;t change anything else, but I can now safely turn on my sub when I'm playing vinyl with no excessive pumping.

Go figure.

Bob