The Gristleizer is a legendary effect, designed by Roy Gwinn in the 70s and made famous by industrial music group Throbbing Gristle. See here for more Gristleizer information, courtesy of TG's Chris Carter.
This effect combines a tremolo with an oscillator-controlled filter. The controls allow considerable versatility, allowing you to achieve sounds from polite, smooth tremolo and auto-filter wah wah sounds, to industrial grinding distortion, ring modulation, and hard stuttering effects.
Starting with the original design, some modern conveniences have been added. The audio and control circuits remain the same, but a flashing LED was added to show the speed of the oscillator, and a charge pump IC to allow the PCB to be powered from a single battery or standard 9v pedal power supply. Also included is the option to bring the bias trimpot out to the front panel for more versatility and tweakability.
The pots can be board-mounted, cutting down considerably on offboard wiring time. They can still be offboard if you prefer. The Gristleizer has a silkscreened component legend to make the build fast and simple, soldermask (blue) to prevent solder bridges, and plated pads so you don’t need to worry about cold solder joints.
Click here to download the Gristleizer build PDF. This file includes wiring diagrams, schematic, bill of materials, and details on adding useful mods. Please right click and save this file to your computer, rather than opening it from the site each time you need to check something.
Here’s a thread with questions, answers, photos and build reports for the Gristleizer PCB.