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Thanks Jim, I'm still messing around and messing things up. I get it going good then I try to improve it and then back to the drawing- uh I mean circuit board. I'll try to keep this short as...

schenkadere- probably not worth all the trouble I've put into it but there is something to the challenge of making a crappy $75 amp into a single ended all tube amp- if it sounds good! I allready...

Jim
You are telling me I should be using the stock 470 ohm R18 screen grid resistor? I guess I wasn't clear on that. I had changed to a 1K and that seemed to work fine. I may have to use that...

Jim P- I'm still around trying to make something out of this cheap amp. I put a 4.7K on the screen grid and soldered it to R25 on the R26 side. I also put 280 ohm cathode bias resistor on EL84. My...

Yes the question about R16 going to 10K (or 5K) was meant for you. I think you were the only one who mentioned it. I realized later you meant R18 after re-reading the whole thread and checking the...

Thanks for the info Goonrick but I really don't want to mess with the filter caps and I have no replacements for them (nor can you get them in this town) so I think I'll try a 4.7K grid screen...

So you can decrease the voltages on the EL84 by increasing the cathode bias resistor? I'm still over 330 volts on the plate and screen grid but the amp works fine. I see the cathode bias resistor...

Rock Mumbles
You got me thinking. R7 is the grid load resistor for the next triode. I wired in at R7 going to ground so it's still in the circuit. Classic designs all use the vol pot for the grid...

Rock Mumbles
The answer to your first question is basically yes. I left in R10 (now 47K) and R11 (1 meg) and went straight into pin 7 V1B. R1 and R2 were bypassed/removed. From there out of pin 6...

Jim P
Thanks for the good suggestions. I will give them a try. Unfortunately, both the vol. and tone pots have failed mechanically- be careful with them. I can't get in touch with Loud Tech. ...

Ok I now have a tube amp with a new/better speaker. This thing sounds great distorted but I can't get any clean headroom out of it. Can anyone help me? The op-amp circuit is gone. The tone...