Post by teleric on Mar 25, 2011 9:27:43 GMT -7
So I'm jammin' with my band mates last night - running the 6545 @ 16 ohms with a Marshall 1960 4X12 cab (the 6545 head is sitting on top of a road case, not on top of the speaker cab). I'm running it relativley hard (gain 12:00-1:00, master vol @ 10:00-11:00 on the 65 side - KT side is esentially 3:00 across the board).
The 6545 was purring along for 2 hours and then mid-song (while playing on the 65 side), the volume drops drops by about 50% - no real degredation in tone (the bass was a little less pronouced, but I think that was fletcher/munson related), but I could hardly hear my guitar over the others - the volume was significanlty lower. Our other guitar player stopped playing and was wondering what happened (so he noticed the volume drop as well). Anyway, I flip the power switch off for about 5 seconds, and turn it back on & the volume comes back to "full volume" (or 100% of pre-dropout levels). I was using my pedal board, but I don't think that was the culprit as powering off/back on solved the issue. After the re-start the amp performed flawlessly for another hour.
So now I'm trying to figure out what happened with my 6545. I think it's either the rectifier tube or a bad EL34 (my first guess is the rectifier since the tone didn't change - but it didn't blow the fuse). I'm running a NOS 5AR4 tube and winged C EL34s (which have about 100 hours on them). I've got a few other NOS 5AR4s on hand, so I'll prolly just switch that out before trying new power tubes.
I'd like to find the culprit as I gig with this amp regulalry and I'd rather not have this happen while gigging.
Any thoughts?
The 6545 was purring along for 2 hours and then mid-song (while playing on the 65 side), the volume drops drops by about 50% - no real degredation in tone (the bass was a little less pronouced, but I think that was fletcher/munson related), but I could hardly hear my guitar over the others - the volume was significanlty lower. Our other guitar player stopped playing and was wondering what happened (so he noticed the volume drop as well). Anyway, I flip the power switch off for about 5 seconds, and turn it back on & the volume comes back to "full volume" (or 100% of pre-dropout levels). I was using my pedal board, but I don't think that was the culprit as powering off/back on solved the issue. After the re-start the amp performed flawlessly for another hour.
So now I'm trying to figure out what happened with my 6545. I think it's either the rectifier tube or a bad EL34 (my first guess is the rectifier since the tone didn't change - but it didn't blow the fuse). I'm running a NOS 5AR4 tube and winged C EL34s (which have about 100 hours on them). I've got a few other NOS 5AR4s on hand, so I'll prolly just switch that out before trying new power tubes.
I'd like to find the culprit as I gig with this amp regulalry and I'd rather not have this happen while gigging.
Any thoughts?