PRS Archon 25 combo amp Volume Drops

[Farmer]

Hello everyone, I'm a newbie here. I have an Archon 25 combo amp that drops volume on the lead channel after 15 minutes or so. Then a few minutes later, the volume will pop back up. I tested all the tubes on a B&K 707, and they all pass. No shorts or grid emissions, and good life expectancy. With the chassis on the bench, I have been tapping various locations on the board while playing, but that doesn't give me a clue to the location of a possible loose connection. Does anyone have an idea if there are any particular components I should suspect? Thanks in advance!

 

[Farmer]

Thank you for the quick reply.

 

[bodia]

Hello everyone, I'm a newbie here. I have an Archon 25 combo amp that drops volume on the lead channel after 15 minutes or so. Then a few minutes later, the volume will pop back up. I tested all the tubes on a B&K 707, and they all pass. No shorts or grid emissions, and good life expectancy. With the chassis on the bench, I have been tapping various locations on the board while playing, but that doesn't give me a clue to the location of a possible loose connection. Does anyone have an idea if there are any particular components I should suspect? Thanks in advance!

I had this problem a couple of decades ago with a Marshall. It happened a couple of days after I bought it, so I took it back and exchanged it for another one. Same thing happened with the new one. Turned out to be dirty power in my house. Not sure if that applies to what you are experiencing, but the symptoms are the same.

 

[Farmer]

That's interesting. I'll look into it. Thanks!