The layout of a musical instrument isn’t arbitrary, it’s a combination of the physics involved and what is optimal for actually playing music. That’s why you can play a scale on a guitar between just three frets on the six strings, and why you can use the same finger positions to play a chord anywhere on a piano. The limitations are only a result of the requirement for physically constructing the instrument, but synthesizers and MIDI controllers aren’t subject to that. Kord Kontroller takes advantage of that fact to lay out notes and chords in an intuitive way.
Most synthesizers and MIDI controllers, by default, have buttons mapped in a way that makes sense on paper. They may, for instance, have the notes of a scale laid out linearly as the pitch rises. But, as anyone who has studied music theory will tell you, that’s not how chords are actually played. Major chords on a piano can be played by using three fingers with two keys between each, and your left-most finger on the corresponding key, like G for a G Major. To switch to an F Major, you just move your hand so your left-most finger is on the F key.
Kord Kontroller makes it even easier; you keep your fingers on the same buttons, and simply use your other hand to switch between keys. If you want to add a fifth, you just push one more button that is always in the same position no matter what key you’re playing in. Kord Kontroller has different modes built-in for finger positions and the layout of the key-selection buttons, which suit different styles of music.
That’s all powered with an Arduino Leonardo, which acts as a MIDI interface to whatever you want to use to actually generate the sound — like synthesizer software running on your computer. The buttons are Adafruit Trellis 4×4 modules, and there are four of them for a total of 64 individual buttons. The enclosure is 3D-printed from Electronic_Grenade’s LaunchPad Housing design. Kord Kontroller isn’t available for sale, but you can use the provided code to build your own.