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Soooo... I built this amp for a buddy in a cheeeeap chinese amp, hoping to reuse the chassis and faceplate and speaker (maybe). My intention was like- i'll save you the details- a deluxe reverb with no normal channel and the belton digital reverb box and modern grounding, pre caps at the nodes, etc. Big exception was that there was no space for a tube rec, which is perfect, because my friend plays pretty confident, not saggy styled stuff. I knew I'd be pushing it on voltage but planned to specify the JJ 6v6 only or 6l6s and used 1k2w screen grid res. So yah, triode DR pt, tf-110 ot...
Everything but the reverb- which I'm still working out- went on the team perfectly. Every power up test, hole and fitment went as planned and assembly couldn't have been sweeter for cramming all this into such a tiny box- about blues jr size. Hitch: the EHX 6v6s i had around for tester tubes (the jjs aren't ordered yet for apparently serendipitous reasons) were drawing massively uneven bias (2:1!!!) and obviously the results hummed and weren't very impressive. Also, because I only have three 12xxx tubes in the amp, there's a missing .9a from the heater chain, and the voltage was about 6.8. Still within 10% (barely!) but uncomfortable, as my buddy's gonna shove all kindsa $$$ Syllardfunken tubes in there.
I have a set of ge6l6 reissues (why do those tubes have a bad rep?) around so I popped them in and biased it about 14w a plate. heater voltage is now spot on. Plates at 450v.
plug in the ol les paul.. HOLY CRAP IT'S TONE CENTRAL! Confidently loud, clean, sparkly, nasty when pushed, all that BS- another great "fender". You know how a really really good amp doesn't need reverb or effects, or even too much gain and you still want to play it?- even through your ev 12l particle board test cab? Thats it.
But, is it not going to last? Or will it last forever? Everything about this project says I was going to ask too much of the 6v6- even the JJ- but 6l6s should just be gliding along. But, what about the trannies?
I played it for about an hour at mid volume and the pt got warmish- ie warmer than room temp- and the ot didn't really have much perceivable change in temp, but the chassis was on the bench, not in it's little hellish box. The ot is rated for 80madc per side, so I'd think everything is on the team. I liked it biased a little hotter, about 40 ma per side (total draw, ie cathode current) but didn't run it long at that setting.
So, how would one make these decisions? I guess i'm not asking for somebody to tell me it's ok as much as tell me how to discern that myself.
THANKS!!!!!
Everything but the reverb- which I'm still working out- went on the team perfectly. Every power up test, hole and fitment went as planned and assembly couldn't have been sweeter for cramming all this into such a tiny box- about blues jr size. Hitch: the EHX 6v6s i had around for tester tubes (the jjs aren't ordered yet for apparently serendipitous reasons) were drawing massively uneven bias (2:1!!!) and obviously the results hummed and weren't very impressive. Also, because I only have three 12xxx tubes in the amp, there's a missing .9a from the heater chain, and the voltage was about 6.8. Still within 10% (barely!) but uncomfortable, as my buddy's gonna shove all kindsa $$$ Syllardfunken tubes in there.
I have a set of ge6l6 reissues (why do those tubes have a bad rep?) around so I popped them in and biased it about 14w a plate. heater voltage is now spot on. Plates at 450v.
plug in the ol les paul.. HOLY CRAP IT'S TONE CENTRAL! Confidently loud, clean, sparkly, nasty when pushed, all that BS- another great "fender". You know how a really really good amp doesn't need reverb or effects, or even too much gain and you still want to play it?- even through your ev 12l particle board test cab? Thats it.
But, is it not going to last? Or will it last forever? Everything about this project says I was going to ask too much of the 6v6- even the JJ- but 6l6s should just be gliding along. But, what about the trannies?
I played it for about an hour at mid volume and the pt got warmish- ie warmer than room temp- and the ot didn't really have much perceivable change in temp, but the chassis was on the bench, not in it's little hellish box. The ot is rated for 80madc per side, so I'd think everything is on the team. I liked it biased a little hotter, about 40 ma per side (total draw, ie cathode current) but didn't run it long at that setting.
So, how would one make these decisions? I guess i'm not asking for somebody to tell me it's ok as much as tell me how to discern that myself.
THANKS!!!!!
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