Available as an assembled Module and as a DIY project.
No info about availability.
Drum module
Doof is not another 808/909 clone. The topology is common enough in many drum synths: Trigger circuit, envelope follower, VCO, VCA, but the actual sub-circuits are slimmed down versions of the dual OTA VCO and VCA from the Matrix Mixer. Very wide ranging and shape control squares up the waveshape to get a nice raspy rattle to the sounds.
http://nonlinearcircuits.blogspot.com/2016/03/doof-drum-module.html
3 Users are observing this
These merchants probably sell this module. Huh?
Nonlinearcircuits Doof