interesting you mention diodes...
in my BUZZ BOX synth, since the housing is a clear ornange rubbermade container, i decided, "hmmm, let's experiment with LEDs, this would look cool lit up inside!
well, i found while placing them in the variable and negative pins of the potentiometers, the signal was increased...SWEET!
then i started to think of why....and i remembered, "well, these are diodes after all". LOL!