Question Abrupt feedback when adjust volume at preamp

Sep 8, 2019
2
0
10
0
Hoping to get some help, as I'm somewhat of a novice and I'm not sure what to search for.

I am using older Sony Preamp (TF-2000F) to a Sony Amp (TF-3200F). I have a single speaker wired to the amp for testing purposes. The Amp has no volume control. When I adjust the volume at the preamp, the speaker emits an abrupt feedback (kind of like a crunch). Note that this only occurs when I have audio signal coming into the preamp. Otherwise, without signal, changing the volume just produces minor static at the speaker.

The original manuals don't offer much in the way of troubleshooting, and I don't see any other settings that I should change. Any ideas? Thanks!
 
You don't mention if you are actually getting audio along with the "crunch"?
Does it happen on both channels?
To determine whether the preamp or amp is at fault you would need to connect a source with variable output directly to the amp or try another preamp.
Since you have a dirty volume pot the other switches and pots may be dirty too. You would need to use the correct chemicals to clean them properly but you can try operating each pot and switch 20-30 times with the preamp powered down. Sometimes they will clean themselves.
 
Sep 8, 2019
2
0
10
0
Since you have a dirty volume pot the other switches and pots may be dirty too. You would need to use the correct chemicals to clean them properly but you can try operating each pot and switch 20-30 times with the preamp powered down. Sometimes they will clean themselves.
I tried switching the volume as you suggested, and it seems to have cleaned it right up! Thank you!
 

ASK THE COMMUNITY

TRENDING THREADS