This is my goto Bass drum. It was one of my first builds. It’s bassed on a 808 bass drum. Has CV inputs for pitch, decay and distortion. Overall it has a nice sound and it can be distorted. Great for techno bassdrums.
http://www.hexinverter.net/mutant-bassdrum
Difficulty to build: Medium to hard, has multiple pcb’s and takes some time to build.