Fulltone Ultimate Octave Clone

[zosotone]

I'm making a clone of my UO pedal. Sounds nice but I wanna make it in a 125B and with some modifications.





It's based on the Foxx Tone Machine with some differences. All pots are 100KB, transistors are CEN2N5172, some different caps in the tone stack and four germ diodes.

I read that the first versions (90's) of the UO had BC108C transistors and 50K B pots.

The original Tone Machine has four 1N34A diodes and I have seen that in my UO the board has four diodes (germanium?) with black case.



Can anyone help me identify these diodes? Maybe OA91's?

[zosotone]

I upload the original Tone Machine vero with the UO modifications: