Testing 1, 2, 3.
Soldered wires, knobs and switches, joysticks, cmos NAND gate.
transparent acrylic front panel and ikea photo frame enclosure
finished
finished
Google for 'NAND synt' or 'lunetta synth' if you want to make something simular. Or buy the excellent book 'handmade electronic music' by Nicolas Collins.
Good explanation on how it works and how to make it at misusage.
Lunetta forum for advanced techniques.