capnkid
Optimus Prime
it gets this faint frequency squeal that goes up and down. i'm thinking the crackeling could be any tube sockets or connection, but what is the whisltly buzz? Tranny going bad maybe?
ido1957
9K Gold Member
Haha - tranny that's a good one! 
I had some intermittent cutting out and volume loss and took it to the shop and had all new tubes installed (Marshall JCM900). Seems to have made a difference as it's not cutting out any more. I think it might have been a pre-amp tube. Jiggling the pre-amp knob seemed to help sometimes. I don't use the mains/speakers/tubes much. I just leave it on standby and pass the signal through the line out to the board, unless I'm recording. For some reason the line out works without the mains having to be on (i.e. while on standby). So, try some new tubes maybe....
I had some intermittent cutting out and volume loss and took it to the shop and had all new tubes installed (Marshall JCM900). Seems to have made a difference as it's not cutting out any more. I think it might have been a pre-amp tube. Jiggling the pre-amp knob seemed to help sometimes. I don't use the mains/speakers/tubes much. I just leave it on standby and pass the signal through the line out to the board, unless I'm recording. For some reason the line out works without the mains having to be on (i.e. while on standby). So, try some new tubes maybe....
B
boingoman
New member
It sounds like a bad tube to me.
Pull out the preamp tubes one by one, starting with the one closest to the input jack. When the whistling goes away, replace that tube. Alternatively, tap them with a pencil. The bad one should be pretty obvious.
Pull out the preamp tubes one by one, starting with the one closest to the input jack. When the whistling goes away, replace that tube. Alternatively, tap them with a pencil. The bad one should be pretty obvious.
capnkid
Optimus Prime
yeah, I ordered some new ones. JJ's all around.
I hope that's the problem, the amp was dirty when I bought it, I just put a new weber in it too.
I hope that's the problem, the amp was dirty when I bought it, I just put a new weber in it too.