Bad tube question?

[npsiwak]

Ok, I am sorry if this is a bit of a retread thats been done a million times, but I wasn't getting much luck with the search feature.

My church has a 2x12 Deville that weve had for a number of years. Just recently it started going on the fritz, with the output volume from the amp dropping to almost nothing. Right now, when you play through it you hear a faint 60 Hz hum, and a very muffled sound of your guitar coming through the speakers. When you turn the gain up high enough it hums and squeals on both the clean and drive channels.

I looked at the power tubes (6L6) and one glows a little brighter blue when its on compared to the other. I havent fiddled with servicing tube amps much to know exacrtly what i should be doing...You all think this sounds like a bad power tube?

[sickboy79]

The sysptoms you describe sounds like it needs new power tubes. I'd start there. Pre-amp tubes can also sometimes cause goofy problems like that. If the power tubes don't do the trick - then try subbing a known good preamp tube at each position until the problem goes away.

[npsiwak]

Thanks for the tip, gettin some 6L6s today to try em out