...and it's NOT the tubes this time.
I know this because before I retubed the amp, I "tested" all the tubes I was going to use in another amplifier and they all worked fine.
Basically what's happening is about 15-20 minutes after I've got the amp running, the distortion channel starts crackling, sputtering, and cutting out and the problem gets worse until the distortion channel fails completely. The clean channel, however, is totally fine! Switching, reverb, effects loop, all cable connections etc are fine... the problem is in the amp itself.
Some of you may remember my other problem I had with the amp: The official diagnosis from carvin was that an output tube failed and took some other components with it in a very smoky, smelly manner. Read about it here: https://forum.seymourduncan.com/showthread.php?t=102350 I have to wonder if my current problems are left over from that situation or due to the kind of repair they did. The attenuator I use was called into question on that thread, but to be honest I got what i felt were good arguments from both sides as to whether the attenuator exacerbated the problem or not. Carvin's engineers told me the attenuator was not to blame.
I'm driving the amp down to the Carvin factory in San Diego over the weekend to turn it in for repair. I am starting to think about new amps, too.
Anyone got any theory as to what's going wrong?
I know this because before I retubed the amp, I "tested" all the tubes I was going to use in another amplifier and they all worked fine.
Basically what's happening is about 15-20 minutes after I've got the amp running, the distortion channel starts crackling, sputtering, and cutting out and the problem gets worse until the distortion channel fails completely. The clean channel, however, is totally fine! Switching, reverb, effects loop, all cable connections etc are fine... the problem is in the amp itself.
Some of you may remember my other problem I had with the amp: The official diagnosis from carvin was that an output tube failed and took some other components with it in a very smoky, smelly manner. Read about it here: https://forum.seymourduncan.com/showthread.php?t=102350 I have to wonder if my current problems are left over from that situation or due to the kind of repair they did. The attenuator I use was called into question on that thread, but to be honest I got what i felt were good arguments from both sides as to whether the attenuator exacerbated the problem or not. Carvin's engineers told me the attenuator was not to blame.
I'm driving the amp down to the Carvin factory in San Diego over the weekend to turn it in for repair. I am starting to think about new amps, too.
Anyone got any theory as to what's going wrong?
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It's highly unlikely that power tube failure and the associated frying of components (which is real common) would have any affect on the preamp section, unless it damaged the heater windings in the power Tranny.... and that's a pretty far stretch. I'll take a glance at the Legacy schematic tomorrow when I get to the shop.
