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« on: February 19, 2021, 01:25:35 PM »
I built a working Uber Tuber from the original version when it was released. It has a warm clean sound with very little distortion unless the incoming signal is high. I noticed today there had been a 1.1 revision to the build doc not long after it was released, and saw that two trimmers were put in to replace the 100K resistors for the plate voltage. The build doc suggests setting the trimmers to bias at about 12 volts, but there are comments that most of the tubes work OK over a bit wider range.
I checked the plate voltage on my board and they are both running over 17 volts using the 18 volt Dunlop power supply. Would changing the resistors to drop the voltage to 12 change the sound from the tube to possibly add more use to the drive/cut/sat controls? If not, is there a reason not to leave the board as-is with the higher plate voltage?