Tube Amp Archive

Success at last! I double-checked the grounding, measured all the resistors and caps again, but in the end the culprit was the gain pot. I replaced it with a fresh new one and now the voltages are spot on and the hum is gone. Big thanks to everone that helped!

Try moving the shielded input cable directly to the tube socket. At least, the resistor should very close to the socket, without a long leg. Yes, that makes sense, thanks. The reason I soldered it like that is because of the Ceriatone layout. I did have my doubts, but decided that there must be som...

Wow. I mean. After staring at these photos for a while, I have no new insights for you. Sorry to hear that. I know it is butt-ugly and I can not really say anything else but I am still learning. This is the third tube amp I´ve built and the first one not from a kit. Perhaps I´ve bitten more than I ...

Hi again! Dropped by the amp again and managed to snap few pics. I´m no photographer and it was difficult avoid reflections and shadows, but I hope these are of some help. https://i.imgur.com/JQ4vpwU.jpg The whole amp in all it´s glory https://i.imgur.com/BUJjCKw.jpg V1 and V2 As you can see, it´s n...

I woke up early and dropped by the workroom on my way to work. I measured all the resistors and caps around the V1 once again and everything was correct. I also measured the decoupling caps for DC leakage, but nothing there either. However, when I measured the V1A grid (pin 2), I found a strange thi...

No no no, I´ve done it again :x This is not my day, it is the V1A that is the problem! You must think I am an idiot and TBH, I would not blame you. But yes, the problem is with V1A , I swear! How about post a photo of V1 components? I don´t have the amp here at home, it is in my rented storage/workr...

Ouch, it seems I have made double accounts! This is not going well at all...

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I would unsolder one end of all the resistors dealing with that tube and confirm there value is correct for starters. With over 10 volts on the B side cathode that tube should be near burning up! Aaand there I go, messing up my very first post :oops: I should have written V1A cathode of course. I g...