This project isn’t really a prototype, but a tool for prototyping. [Tymkrs] came up with a unique way to build this synthesizer prototyping tool. They actually patched into the underside of the breadboards in order to keep all of the permanent bits nice and tidy.
In the clip after the break you’ll see all of the build photos that lead up to this point. After cutting out and assembling the wooden pieces for the case they grab a soldering iron and get to work. Two octaves worth of keys were pulled out of an electric keyboard. Ribbon cable is soldered onto each key’s electrical connection, with an SIL pin header as a connector. This mates with another ribbon cable with a SIL socket on one end, and an IDC connector on the other. The real trick is getting that IDC connected to the breadboard. They cut back the adhesive tape on the underside of the board and soldered a surface mount pin header onto it. This way the inputs from the keys, as well as a few 1/4″ jacks from the back of the case are always available in a tidy way on the breadboards. The video goes on to show preliminary synthesizer work on the device.