
Farview
Well-known member
One 12ax7 was the phase splitter, one was for the reverb and the other three were preamp tubes. If I remember correctly, one was for the 'clean' channel and the other two for the distortion channel.farview.
Not to hijack this thread with a completely off topic question but I gotta ask this question to somebody and frankly, you are the only person on the internet I'm aware of who MIGHT be able to answer it.
I realize you worked on KMD amps (presumably the xv100sd head) ages ago and you might not remember technical stuff about the amp but I need to ask:
I recently bought one of those. I'm a newb and dont know much about amps technically but I notice it has five 12ax7 tube sockets. 3 on the left and 2 on the right. (looking at it from behind). Are all of them preamp tubes or is one for the reverb or some other thing or what? Should I use 12ax7's in all those? (mine has no tubes right now). Which one is "v1, v2 etc"?(when looking at it from the back).
Also, do you remember what that "hum balance" knob on the back does? never saw one of those before. I would imagine it has something to do with hum???
And do you remember what the plate voltage on that amp generally runs?
Disregard if it was too long ago to remember. I dont remember crap from 20 years ago.
You need to put 12ax7's in all those sockets and 6550's or kt88's in the power tube sockets.
I have no idea what the plate voltage should be. Check the tube specs, KMD wasn't known for taking design chances.
That amp had kind of a Marshally sound to it. At least until you stuck it next to a real Marshall.
The hum balance control was used to dial out the hum, just twist it until the amp is its quietest.
BTW, that was the good KMD amp. That doesn't say much.