Schematics / VCA-Inverter-Overdrive
VCA/Inverter/Overdrive by Jürgen Haible .Visit his page for various schematics http://www.jhaible.de/additional_schemos.html ,on this module he wrote :
One input is routed to the output via two separate paths: One VCA with zero to positive unity gain (approx.), and one manually adjustable path with zero to rather high negative gain. The output voltage is clipped by a set of zener diodes, so the module can also act as Overdrive / Distortion device.