[Keith Baxter] has undertaken something of a ‘Mount Everest’ of guitar modifications. He’s developing a Servoelectric guitar that trades frets for a keypad. It is still a guitar in the sense that it has a body, strings, and pickups to sense the strings vibrations and pass them to an amplifier. The left hand, which traditionally would shorten the strings as needed by pressing them against a fret, now changes string pitch using a keypad. This is an interesting fusion between traditional guitar and 80’s phenomenon, the keytar.
Each string is connected to a different servo motor. When a key on the keypad is pressed, the corresponding servo adjusts the tension of that string, bringing it in tune at the new pitch. His original design involved a lot of custom circuitry but he’s evolved the project to include an Arduino controller. This second generation both simplifies the control circuitry and improves upon it.
We’ve embedded some video after the break. In the first example you can see the strings adjusting for each new pitch. In the second, take a look behind the guitarist… what do you think he’s got planned for those giant capacitors?