Judging from the video (found after the break) the Nebulophone is one of the best sounding DIY synthesizers we’ve seen. Especially when you consider the simplicity of the hardware design. It uses an AVR chip and an OpAmp. The rest of the parts are just a few handfuls of inexpensive components.
The device was developed by Bleep Labs, and they sell the synthesizer kit seen on the left. But since it’s an open source project you can follow their design to fabricate your own, which is what [BlinkyBlinky] did with his offering seen to the right.
An ATmega328 drives the device, which is the chip often used in the Arduino Duemilanove. The keyboard is a set of traces hooked to the microcontroller. These are tinned pads on the kit PCB, but the DIY version simply uses some adhesive copper foil with a jumper wire soldered to it. The keys are played with a probe that makes the electrical connection, a common practice on these stylophone type designs. Chances are you have everything on hand to make this happen so keep it in mind for that next cold winter weekend that’s making everyone a bit stir crazy.