This is a simulation of the good old transistor distortion stomp box. It accepts a mono input and is used as an Insert or Send Effect. The effect does not use the standard VST effect interface; to open its parameter window you have to click the Edit button in the Send Effects or Channel Settings window.
The Electro Fuzz has the following parameters:• Boost
This governs the amount of distortion. If you want to increase the distortion without raising the signal level, you may have to adjust the Volume knob as well.
• Clipback
Raising this parameter will “invert” the part of the signal that is above the clipping level, instead of employing hard clipping. The result is that more 2nd order harmonics are added, changing the character of the distortion.
...it will be clipped like this.
Increasing the Clipback value... 
...will invert the clipped signal peaks, adding harmonics.• Volume This is a volume control for the output signal from the Electro Fuzz.