Crowther Audio '03 Hot Cake

I laid out the original 1977 Hot Cake a while back, but never got around to doing the modern one that came out in 2003. So here's the newer one. I ignored the original relay bypass switch and the polarity protection diode could be replaced with a 1N4001 or similar. The original 1N5238 is an 8.2v zener. It's laid out for board mounted pots as usual, and should be an easy fit in a 1590B. Here's the schematic for reference. There's also now a fabricated board for this circuit available in the store—the Crempog.

Crowther Audio Prunes & Custard

The Crowther Prunes & Custard is a unique distortion box good for both guitar and bass. It's a two-stage circuit, built around a TL072 dual-opamp. The first stage acts as a preamp, and the second stage generates the distortion, with harmonic overtones. I've laid this out for on board pots (long leg PCB-mount pots will probably work best mounted from the component side) and it should fit nicely in a 1590B enclosure. The 2 switches are SPST.

Crowther Audio '77 Hot Cake

A lot of awesome things came out in 1977: the op amp version of the Big Muff, the grey box DOD250, Fleetwood Mac's Rumours, the Sex Pistol's Never Mind the Bullocks, and STAR WARS (May the 4th be with you). The Crowther Audio Hot Cake also made it's debut in 1977, and you could say it was one of the first "boutique" stompboxes ever made. It featured an 741-type IC and a unique way of bypass switching. To quote Steve (bajaman) from FSB:

It used a 120k resistor and simple shorting switch from the bottom of the drive pot, 1k, 470p, 12n, 12n, and bottom of the level pot, to earth. When the switch is open all the foregoing components were lifted by the 120k resitor - hey presto bypass mode. When the switch is closed: bingo, tons of boost.

To add an LED on/off indicator, I would suggest using a DPDT switch. One side can be used to bypass the effect, and the other side for the LED. 

As many know, an updated version of the Hot Cake was released in 2003. This has a presences control instead of the mids lift/normal switch in the original, and has a more Fender-like sound compared to the Marshall-like sound of the original. Many say that as you turn the drive control up, the tone gets muddy, but with the volume cranked and lower drive settings, the Hot Cake really shines. I've added a polarity protection diode, a power filtering cap, and a resistor for the LED on the board. For more info, check out the FSB summary page. I've also created a fabricated board for this circuit in the store—the Crempog.