Nude Turntable Project

Henry, are you sure the feedback comes through the shelf? Could it be airborne direct to the cartridge?

It cannot be air-borne feedback Aigenga....
The stylus is in the groove with the turntable motionless and no music coming through the speakers.
When I turn the volume up to a very high level...a low frequency drone begins and then increases in volume without further manual volume input.
The feedback begins when the room is in silence...🔇

Henry,
I suspect the coupling - 3 rubber grommets are the root of this evil. It won't matter how much mass or how stable the base is, if the coupling is inadequate.

Can't say I have a solution, but I'd try something like a thin bead of silicon caulk, or possibly the sealer they use to couple a speaker driver to a cabinet. I wonder what Mosin uses to couple Saskia to the slate plinth.

Regards,

Now that I see your last post, what you're describing is a low frequency oscillation (gets louder). If the stylus is stationary, does this originate in the table or preamp?

I went back to my original set-up from 2 years ago and guess what........
No feedback.....🎉😍
Then it dawned on me......
Has it dawned on you.....😜❓