Try disconnecting your turntable from the phono pre and short the individual phono inputs (not to each other). If it still thumps, it’s likely the phono pre has a bad tube or is going bad.
turntable " thump " sound when not running
Hi I have a question that’s been in the back of my to do list for the longest time so I decided to join the forum after reading so many postings over the years from this legendary community. :) I have a thump sound the same way it sounds when dropping the stylus on a record. it occurs about every 10-20 seconds or so regardless if the turntable platter is spinning or off. I am guessing its electrical? what causes this? I have a pretty decent setup yet modest compared to most of you guys in here and I think I shouldn’t have to deal with this thumping sound. By the way this sounds only occurs on the phono. the cd, tape, etc doesnt have this problem.
Adcom GFP-750 preamp
Adcom GFA-555II amp
Jolida JD9 II
Music Hall 5.1SE TT (Sumiko Blue Point no. II)
LSA-1 Statement speakers
I have the turntable power supply adapter plugged into the back of the preamp power ports.
Should I move it to a different outlet? Maybe I just answered my own question.
Adcom GFP-750 preamp
Adcom GFA-555II amp
Jolida JD9 II
Music Hall 5.1SE TT (Sumiko Blue Point no. II)
LSA-1 Statement speakers
I have the turntable power supply adapter plugged into the back of the preamp power ports.
Should I move it to a different outlet? Maybe I just answered my own question.