Hi, I have traced some schematic from a PCB (RYO optodist), because I wanted to learn how voltage controlled distortion works. I understand most of what’s happening, but I do not understand how the vactrol LEDs are driven.
If I got this correct, then the CV signal comes from the left through a 68k resistor and is then mixed with the gain pot (upper voltage divider between 12V and 0V) and a gain trimmer (2k and then a 100 ohm resistor, see lower left). This goes into a pnp common collector amplifier (correct??) which then controls then second transistor which drives the LEDs?
But doesn’t this mean that I get more gain in the first transistor (and hence brighter LEDs) when I lower the CV voltage? This seems counter intuitive! Did I make a mistake in my schematic?
I don’t really understand how the transistors work in this configuration, can anyone explain?