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Attached for reference is a copy of the Ampeg GV-22 schematic that I have in my files.
Ampeg GV-22 Schematic.pdf
Ampeg GV-22 Schematic.pdf
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No I can't measure watts from the output. I probably have the tools here but I don't know how. I have "shop" tubes though. Let me try replacing the V1 just to see how that effects the current. Update: yes one of the tubes was bad. I replaced it with a random "Groove tube". That brought them in better alignment with .045/048 ma. I'll press the customer to get a new match pair. BUT I swear that the tremolo/vibrato are working even better now. Could that bad 6l6 tube effect the tremole??Last edited by mikeskory; 03-13-2023, 05:45 PM.Comment
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Maybe not a "bad" tube but definitely not a good fit for the GV-22 in it's current setup. The current idle tube dissipation is right at the limit that I would allow. If you buy a new set then perhaps you could get them from a source that grades them such that they will run cooler in your amp. The other choice is to modify the bias circuit so the tubes run cooler. I think that anything in the range of 32mA to 40mA at 480 plate voltage would be good.Originally posted by mikeskory View Post
I don't have a direct explanation. However, all the circuits in an amp function together as a system and when any one section if out of kilter, other functions can suffer.Originally posted by mikeskory View PostComment
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Just to finish the tale, I got everything working including the trmolo/vibrato.. @g1 I As i said earlier, I installed the new tremolo, all the caps for the Tremolo circuit (like you circled) and cleaned both trem controls and re-soldered the little board that holds the controls. That made the Tremolo come alive but it did have a clunky sound. I reinstalled the old tremolo and it sounded great. AND the problem with the volume was one bad tube. I had an old set of Groove Tubes to test with and it's loud now. Thank you everyone.Comment
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