Modified by Mike Walters, 2002
This was a Yamaha DD-50 drum machine manufactured in 2000. I found it broken at Goodwill, and immediately bought it to mess with the circuits. There's a ton of fun located on one of the main chips, and can be activated by shorting its pins. Originally, I wired one potentiometer, and two momentary switches. That's how it's pictured above. I've since replaced the potentiometer with a rotary switch, and the momentary switches with toggle switches. It's much more stable and better suited for performing.
The sounds are really amazing. The built in "songs" sound like contemporary christian music from the late Eighties. The circuit bends do cool things to these sounds. It's also great to synch with other MIDI devices.