via Tindie Inc (via Laurentide)
"This is a near exact clone of the famous kick drum from the classic tr-808 drum machine. The only changes are for facilitating the common mods (extended decay and a pitch pot), and a slightly more flexible trigger input.
This can be triggered by a trigger output of a drum machine, or by a CV/Trigger from a modular synth, a cmos square wave, or even a loud audio transient. Alternatively you could wire a switch or button to send the trigger input high as well. (Basically a quick +V to the trigger input does the job).
It runs on +/- power supply, you can run 2 9v batteries in series, or run it off a bipolar (+/-15v or +/-12v power supply). Or... experiment!
This is an easy and cheap build - I have a Mouser BOM available here: http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=950b04d9fc
Schematic is here: http://www.anestheticaudio.com/808bd_sc.jpg
Board layout is here: http://www.anestheticaudio.com/files/dimgs/rsz_h369_13_32.png
There is an extensive thread with build tips, etc here: http://www.muffwiggler.com/forum/viewtopic.php?t=54149"
