WOOHOO!!! I can put this baby to bed. Given the cause, I think I'm gonna go ahead and AC couple the input to get rid of the noise. It'll be better for the guy getting the amp.
Many thanks to all. It seems I learn something new with every build. Good times.
Rocket Build...noise issue.
Moderators: pompeiisneaks, Colossal
Re: Rocket Build...noise issue.
It's all about the tone!
Re: Rocket Build...noise issue.
Had a go with my Rocket a little while ago and can report the same thing. I rarely roll off the volume on the guitar, so I never really got a chance to hear it. It's subtle, but there. Remembering this thread reminded me to check. I've never been happier about having DC leaking. 
Apparently, this means it's a properly running Rocket, according to Hogy. 
Apparently, this means it's a properly running Rocket, according to Hogy. Re: Rocket Build...noise issue.
I too was getting scratchiness in my Rocket, it was the JJ 083 valve. I now have roughly 12mV on the grid. Still not sure that is a good thing.
Yours Sincerely
Mark Abbott
Mark Abbott
Re: Rocket Build...noise issue.
Some 12AX7 seem to have more grid current than normal, so it may be worth trying some different ones (another of the same brand/batch may work the same).
It's a bad idea to operate a tube without the control grid having a solid dc reference; if floating it can drift up and even a 12AX7 can redplate (don't ask me how I know!).
Pete
It's a bad idea to operate a tube without the control grid having a solid dc reference; if floating it can drift up and even a 12AX7 can redplate (don't ask me how I know!).
Pete
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