Pete Cornish - G2 Guts, Schematic, Layout (from Tracer's Fund)  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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mookyj
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Post by mookyj »

I find it a disappointment of craft to see what is in this pedal. One could claim craftsmanship for the harnessing, except if designed properly, none would ever be needed. The PCB looks to be old tape and mylar design which may hold nostalgic value but as it is, it's poorly laid out, and poorly adapted for PCB fab, DFM, consistent impedance and minimal return paths. Seriously expected to see far better implementation and execution of design...shame to see something so overpriced and poorly designed. I would say he went out of his way to make it more difficult to reverse engineer it. The goop is a real nice paranoid feature...

If you make it well enough and cheap enough, it makes it not worth the bother for your competitor.

Kudos to the efforts to make sense of it, it surely can be done properly with significant improvements.

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StratWiz
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Post by StratWiz »

Kit Rae resolved the problem, and in order to get the G2 to work with 4 Germanium diodes, and reduce the excessive bass, you need to change at the sustain stage the following resistors
18k @ collector R17 (instead of 15K)
100 @ emitter R15 (instead of 680)
See also:
http://www.bigmuffpage.com/images/schem ... ematic.jpg
And
https://aionfx.com/project/cygnus-distortion-sustainer/
Note: you need to keep the Cornish input buffer since it preemphasizes the signal and reduces its bass.
Attachments
Big_Muff_Overdrive_G2_Schematic.jpg

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