BTW, if you're interested in doing this sort of thing -- 2-wire piezo buzzers from radio shack make good velocity sensitive sensors. I built an electronic drumset out of PVC pipe and plywood and taught myself how to play drums with it.
Yep, that's the entirety of the circuit. This will work with any drum brain I know about (but it's been a few years since I did it, so YMMV...) This worked with an old Alesis D4 that I bought at a pawn shop. And I know it'll work with a DM5, etc etc.
You can play with materials a little for the surface -- I used plywood and mousepads. Mousepads are a little soft (the traditional 3/8" thick foam rubber with a cloth backing type...), Different thicknesses of plywood affect sensitivity, etc. If there isn't enough mass, false/double triggering happens.
It's a fun thing to try, and the materials are really cheap (and there are DIY drum trigger boards you can find on the internet now...)
BTW, if you're interested in doing this sort of thing -- 2-wire piezo buzzers from radio shack make good velocity sensitive sensors. I built an electronic drumset out of PVC pipe and plywood and taught myself how to play drums with it.