Traditional synthesizers use a standard piano keyboard layout. This works well in most situations, but like the QWERTY/Dvorak debate on computers, there is always the possibility of a better way to do things. One such “key” arrangement is known as the Wicki-Hayden note layout, which uses an alternating arrangement of keys to stack major scales on top of each other — within easy “striking” distance.
Like Dvorak layouts, this alternate note arrangement is much less common. As seen in the demo video, however, KOOP Instruments has leveraged the Wicki-Hayden setup to create a stunning dual-pad instrument that looks like a lot of fun to play. The dual input pads are entirely modular and plug into a central control unit using DB25 connectors that are wired to the buttons in a matrix.
The central board contains a Teensy 3.6, plus a number of additional buttons and knobs for control over the sound. After being properly translated, digital audio signals are passed along via a MIDI jack.
The project is well laid out in KOOP Instruments' post you’d like to assemble your own, and Arduino/Teensy code is available on GitHub with print files on Thingiverse. Excluding print time, the build should take around 30-40 hours from start to finish, and you’ll need a fairly large printer like the Creality CR-10 to make the device as designed. Also notable is that the BOM is around $650, mostly due to the 214 Sanwa arcade buttons used here.