CORVUS DISTORTION / SUSTAINER
5
BUILD NOTES
Gain stage modification
The original 1978 Big Muff used a gain setup similar to the original Big Muff: a fixed gain stage with a
volume control after it that attenuate the level before the clipping stage.
Since it uses an op-amp rather than a transistor, it’s better to make the gain itself variable as opposed
to running it full-up and then cutting back the level afterward. So, the Corvus includes a modification
suggested by Analogguru that accomplishes this. C4 is added as a DC blocking capacitor, and the Sustain
control is wired back to the inverting input of the op-amp to control the gain directly.
The stock version of the Corvus uses this modified gain stage, so if you build it according to the parts
list, it will have this improvement. However, if you’d like to build the stock version, you’ll want to do the
following:
•
C5:
jumper
•
R7:
omit (leave empty)
•
R8:
47R
