@response34
That IS interesting. Since the caps pass AC, it’s possible a very high voltage ( >> 30V) turn on thump could occur. However, honestly that would damage the amp even if off. It would most likely break through most electrolytic coupling caps and if DC coupled, short several transistors. Of course, if a speaker was connected, things could get even worse! :)
Perhaps what tube preamps really should have is a coupling cap + zener diodes to prevent the possibility of high voltages reaching outside.
That IS interesting. Since the caps pass AC, it’s possible a very high voltage ( >> 30V) turn on thump could occur. However, honestly that would damage the amp even if off. It would most likely break through most electrolytic coupling caps and if DC coupled, short several transistors. Of course, if a speaker was connected, things could get even worse! :)
Perhaps what tube preamps really should have is a coupling cap + zener diodes to prevent the possibility of high voltages reaching outside.