I found some old 12au6 tubes that were in an old ham radio and they look like they could fit into a marshall pre-amp. does anyone know what that would sound like and if its even possible?
you mean a 12au7? its a lower gain preamp tube.
i dont think its a sin to use non-matched preamp tubes, but i dont think you want to just stick it in randomly into a preamp using 12ax7's.
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