problem with rocket 44

[wilson]

i just got a used rocket 44 from this guy. i tried it out before i bought it but couldn't really crank it up.
just a while ago i had it on the dirty channel with the contour switch on. i had the gain set to about seven and turned up the volume to about four. then as i was playing the volume just dropped really low. now it plays but the clean channel sounds muddy and broken up and neither channel will get loud at all.
any ideas?

 

[wilson]

i took the 12ax7s out of my nomad and put them in the rocket and it didn't fix it. then two of the power tubes started glowing way brighter red than the other two so i turned it off. i moved them around to see if it was the tubes themselves or the location of the tube that was causing it but they acted normal. so i moved them back to the original locations and they didn't glow this time.
i put it all back together and now the amp works fine! the volume level is back to normal. there does seem to be a lot of noise in the dirty channel though.
this is frustrating. if it was a bad power tube then wouldn't the amp not be working at all right now?

 

[MikeK]

It sounds to me like your tube swapping 'cleaned' the connecting pins on the tubes and sockets that needed it and that cleared the problem. Yes, if one of the power tubes was actually bad, you'd still be having the problem.