OKKO Diablo+

The Diablo is a modified BSIAB circuit and the Diablo+ version has an added boost at the output that's independent from the main overdrive circuit. I've laid it out for a 125B with top mounted jacks for a nice small footprint. Originals have a switch to run at 9 or 18 volts which I've left off-board so builders can choose their preferred voltage doubling method. Trim pots are extra controls, not for biasing, FYI.

Boss FA-1 FET Amplifier

Originally a bit of a flop from Boss, the FET Amplifier was made famous by U2's The Edge. It features a 2-band Baxendall tone stack and the Volume control is more like a gain control. Originals use 2 single opamps that are pretty hard to come by these days, so they've been replaced by a dual opamp. Pots are board mounted and it should all fit in a 1590B.

Prescription Electronics Clean Octave Blend

Got a request for this one for Fuzz Friday. Originals fetch crazy prices online. It's an octave fuzz with a clean blend. If you want a fabricated version of this, check out the Corn Cobb on the store.. Schematic over on FSB. Should squeeze nicely in a 1590B.

Lovepedal Super 6

Here's a simple MOSFET overdrive from Lovepedal. Should be a quick and easy build in a 1590B. The board is designed to fit vertically in the enclosure with this kind of pot soldered on alternating sides of the board (Intense and Volume on the component side, Tone on the solder side). Oh, and the electrolytic caps are just lying flat, but not axial types. Schematic, notes and even a 1590A layout here. My layout below is so symmetrical I had to get a fabricated version on store... Here's the description from Lovepedal:

Reminiscent of the mid 60's Blackface Fender era. Specifically a Blackface Super on 6.

Plug the Super 6 in to a ANY clean amp to nail that mid-60's American amp tone. This unit will turn a small amp into a much larger sounding amp instantly.

With an onboard vintage tone stack to die for, you now have ULTIMATE control over ANY guitar / amp / effects combination.

Jersey Girl Fulltender

Took the Boss OD-1 layout from a few weeks ago and put together the Fulltender. It's just a modded OD-1, but with enough changes that a new layout made sense. Great sounding pedal. And if you'd rather a fabricated version, the Odd One Out is available on the store.

Keeley El Rey Dorado

Here's another Plexi-in-a-box overdrive, this time from the great Robert Keeley. It's a cascaded opamp design running on a bipolar +/-9v supply. The Power Toggle as it's known on the original selects between red LEDs or BAT46s for asymmetrical clipping.

Third Man Bumble Buzz

The Bumble Buzz is sold by Third Man Records, Jack White's record store and was designed and built for him by Union Tube & Transistor. It's a modified Kay Fuzz Tone F-1 with 4 silicon diodes in parallel instead of 2 germaniums like the original and the tone control fixed (so there aren't any controls at all). Easy fit for a 1590B and you might even be able to squeeze it into a 1590A.

There's also a fabricated version of this on the store if you prefer. It mounts directly to a 3PDT footswitch so your board isn't just floating in the enclosure and/or you don't have to mess with standoffs or double-sided tape. There's also 3 other new PCBs on the store as well, so go check 'em out!

Benson Preamp

This one just traced over on FSB. It's essentially a modified Wampler Plexidrive with an added bass control. Unless you're really sure any through-hole J201s you have on hand are in spec/authentic, I'd suggest using MMBFJ201s, which are the SMD version which are still in production and much easier to get in spec than the discontinued through-hole version. SMD to through-hole conversion boards here.

Update August 19, 2019:

Corrected a few values that have now been confirmed by Benson. The traces haven't changed however.

Fulltone OCB

What's the OCB you ask? It's the bypass buffer circuit from the new version of Fulltone's OCD. It allows you to switch between regular true bypass and buffered bypass. There are 2 versions: The first (smaller) inverts the phase of your audio signal when engaged (in bypass mode phase isn't inverted). The second (larger) adds an extra inverting transistor stage so that the phase of the output signal is the same as the signal coming in. If you've built an earlier version of the OCD in the past, you can add the 2nd board to make it into the newer version.