Making an Analog Eurorack Guitar Synth with a 1970's Ultra-Fuzz Circuit

I've been exploring some guitar synth sounds using the hard sync input on my VCO, but this has some issues with tracking stability and major noise problems. I solved this be re-building the classic Craig Anderton Ultra-Fuzz circuit from "Electronics Projects for Musicians" in a eurorack format, which is a comparator-based fuzz that outputs a proper square wave rather than a clipped sinusoidal one. This provides much better tracking and dynamics and lets us get those classic screaming hard sync synth sounds out of any guitar.
Ultra-fuzz modernized schematic:
drive.google.com/file/d/1FQu9...
Read Craig Anderton's post on updating schematics from EPFM:
craiganderton.org/electronic-...
Moog MF107:
reverb.com/p/moog-moogerfooge...
A good demo of the MF107:
• Moog Moogerfooger MF-1...

[@soejrd24978]

You inspired me to design and build my own step sequencer, I'm in the coding phase right now and hope to make a video about it :)

[@MV-in8xs]

Nice job - glad to see your work again - this is the guy that bought your DW8000.

[@TheForestHedgehog]

Neat trick to use hard sync! You have an option to pass your signal thru clock divider (as it is a square wave anyway) to get an octave down signal and make a separate signal processing.

[@rodgre]

This is awesome! Huge fan of both Craig Anderton's EPFM book and analog guitar synthesis. This is exactly what I dreamt of doing with a Paia Gnome kit in 1986. Ha!

[@VHS_PAL]

I admire that you're still making PCBs and not telling us about your sponsor JLC... And all in an apartment.

[@dcurry7287]

If he spills any of that ferric chloride, his landlord's going to think he's cooking meth...
which is probably less addicting than synthDIY anyways.

[@jonnymartin6177]

Awesome job! I sold my MF-107 because I couldn't find a good way to get it tracking my guitar's pitch. Nice ingenuity to find a solution to that problem!

[@csselement]

Extralife, the badass genius!

[@woosix7735]

what an awsome idea! learned something today

[@StaticReleaseMusic]

Super Cool! Very inspiring patch! And to think you made a fuzz module to use as a square wave converter... Brilliant!

[@blackseastudiohk]

I like your background music,
Well done with the sharing as well

[@vvuuppee]

great video

[@NotAlrightSpider]

Macauley Clapton. Once you see it, you can’t unsee it.

[@harmless3449]

Dude I noticed right away glad I'm not the only one

[@Magicmoose88]

epic

[@MDJ5]

i bet that extra noise associated with the extra sustain would sound rad through a LPG.