Built a junk box guitar amp. http://monster.partyhat.co/article/micr ... mp-R2B.pdf 12ax7 feeding a 6aq5. See attached schematic. The only changes i made were the 5.6K to the 6aq5 is a 5.1k and the power supply is a full wave since the transformer i had was not center tapped. the buzz goes away when i short the input. What am i missing?
Got it figured out. The Can cap i was re utilizing was bad plus the guitar i was using had a bad ground from the pickups to the jack. Swapped Caps with another one i had laying around and it was quiet as hell.
Guess that's the danger of using used can caps although building a guitar amp from scrap parts that guitar players love is cool. I can't play a chord to save my life but i can build the amps for those who can. Biased a russian Mig 60 last night. The genius got under it ad cranked the bias until the tubes had a catastrophic meltdown. Told the guy he was lucky he didn't burn out the output transformer.
Heh, I had a guitar amp customer like that. When he brought it in for it's 5th set of EL34's in 6 months, I put the bias inaccessible from the outside. He was mad as heck, but didn't have to re-tube for two years!
-= Gregg =- Fine wine comes in glass bottles, not plastic sacks. Therefore the finer electrons are also found in glass bottles.