Lounsberry Nigel

Here's a transistor based overdrive I came across on FSB. Demos sound interesting, so give it ago. Easy fit in a 1590B.

Greer Amps Tomahawk

 Here's a popular drive box from Greer Amps. It's essentially a Distortion +/DOD 250 but with a modified gain control, LED clipping and a treble cut pot. Should be an easy fit in a 1590B.

Hudson Electronics Sidecar

 Here's a really great sounding overdrive from Hudson Electronics. The Sidecar is loosely based on the Tube Screamer with a 2-band Baxendall EQ and some interesting soft clipping. It uses a PNP germanium as a diode along side an LED and a 1N4148 in an asymmetrical configuration. I've got a fabricated version available in the store as well if you prefer and the schematic is over there in the build doc. 

Catalinbread Karma Suture

 Happy Fuzz Friday everyone! This one recently got traced on the Aion blog (so go check out the full write up over there for more info and schematics). The Karma Suture is based on the Harmonic Percolator and has come in both germanium and silicon versions. The difference between the two are just a couple value changes, so you can build either version on the same board. Value differences are outlined below.

 

Bomtempo

 Just stumbled across this on FSB. It's a tap tempo + modulation add on for PT2399 delays designed by Electric Canary. It is digital so you'll either need to buy a pre-programed chipset or burn the code onto the chips yourself. Lots of off board wiring with this, but it's probably worth if you have a favorite PT2399 delay you want to take to the next level. Check out their site for more info, schematic and the code.

Way Huge Red Llama 25th Anniversary Reissue

 Happy New Year, everybody!  This one recently got traced over on FSB. The 25th Anniversary edition of the Red Llama has an added hi cut tone control, but also has a few variations from the original circuit. The hi cut itself is just a basic cap/pot to ground tone control, the minimum gain resistor on the first stage has been reduced from 100k to 91k, and the 2nd stage feedback loop resistance has doubled up from 1M to 2M. Schematic and more info on FSB.

Dirt Master

 Here's a little something I whipped up the other night on a whim. Actually built it on the fly before I even drew up a layout. I was trying to build something with some old mojo caps I found on my bench, and it initially started as a treble booster, but I ended up wanting more gain. Initially it was based on the EQD Arrows, but added an extra cap off the emitter (ala the Rangemaster) for more gain and snarl. I used a germanium transistor with an hFE of around 230. Worked well with a silicon transistor as well. Room for experimenting with the input and output caps. Should fit easily in a 1590B.