DOD: 250
So by this stage, I think we can all assume that I’ll be the only one making this. I have a bunch of tin can LM741 opamps that I forgot about, so I thought why not… DOD 250 / DISTORTION + LAYOUT
DISTORTION PLUS FAMILY
DOD / MXR: 250, Distortion + component values table
This is probably where it all started in terms of opamp-driven distortion – in one side of 741 opamp, out the other with some hard clippers. DOD 250 / MXR DISTORTION + SCHEMATIC Direct link to Google Doc 741 SPECS Numbers vary slightly by manufacturer and grade, but these headline specs are what give the … Read more
GRETSCH: Controfuzz
The Gretsch Controfuzz is yet another variation on the Distortion + the key point of difference this time is the clean blend, which makes this a little different than the rest. This layout does include a mod that increases the 10k distortion control to 100k, as 10k seems to be too small to be workable with … Read more
DAN ARMSTRONG: Blue Clipper
I thought I might finish off layouts for the rest of the Dan Armstrong series, as I’ve already done a few. Anyways, while I was looking at schematics of the Blue Clipper from all the usual sources online, I noticed that the opamp bias looked a bit odd. Then I noticed a few layouts used … Read more
DOD: 250 Overdrive Pre-amp
A nice simple one – the DOD 250, which is a Distortion + variant. Or is it the other way around? Either way, it’s a classic. DOD 250 OVERDRIVE PREAMP – VERO LAYOUT DOD 250 OVERDRIVE PREAMP – SCHEMATIC DOD 250 OVERDRIVE PREAMP – VIDEO DEMO
GREER AMPS: Tomahawk Deluxe Drive
This is a simple one from Greer Amps – the Tomahawk Deluxe Drive. It has some distinct similarities to a Rat or Distortion +, in that there’s opamp clipping, driving hard clipping diodes, and a tone control. Schematic from PedalPCB. I added a buffer on vref, as half the opamp wasn’t being used, so why not. GREER … Read more
CORNISH: SS-3 Modded Diode-Compression Opamp
Details of this project can be found here – as I started with a modded Pete Cornish SS-2 using the Joe Davvisson diode-compression op-amp, and then moved on to this. Essentially the same as the SS-2, but with the addition of a lo-cut. After a bit of testing, I’d suggest a C50k for the sustain … Read more
CORNISH: Modded Cornish SS-2 using Diode Compression Op-amp
This is a Pete Cornish SS-2 using Joe Davisson’s diode-compression op amp. It sounds pretty good – a lot like the regular SS-2, but without any distortion artifacts on sustained notes as it fades outs. It’s also quieter in terms of noise. This one is getting boxed up, and now I want to try a SS-3 … Read more
BARBER ELECTRONICS: Edge Hog
Check out the video, as it includes a tear down, schematic and a great explanation of the Barber Edge Hog circuit by Gray Bench Electronics. He has a few other video that are worth a look too – hopefully more traces to come… BARBER ELECTRONICS EDGE HOG – VERO LAYOUT note that I did … Read more
PETE CORNISH: SS-2, Vero Layout, Modded Buffer, SS-3 Values
Like the very lengthy title below suggest, it’s a Pete Cornish SS-2 with mods. After finishing the SS-3, they’re almost the same, so I thought I would also do a SS-2 layout. Changes Swapped the Cornish buffer for a standard opamp based buffer Ran the reference voltage through the spare opamp Used a quad opamp … Read more