Hitting All the Right Notes
The Marimbatron is a unique digital marimba with an isomorphic key layout that was built from the ground up to be easy for drummers to play.
Oftentimes, the best hacks are born out of necessity. Leo Kuipers is a musician and hardware hacker that wanted to learn to play the marimba. For those unfamiliar with this instrument, the marimba looks a lot like a big xylophone, but it plays much softer tones. Kuipers is an experienced drummer, so sliding over to a marimba may seem like a very natural move. However, in reality the marimba plays much more like a piano than drums, despite the use of drumsticks or mallets to play it.
And that is where the problem lies. Despite a lot of hard work, Kuipers has never been able to learn to play the piano. The solution? Re-engineer the marimba, of course! During the most recent Fab Academy — a hands-on learning experience that teaches students rapid-prototyping and planning skills — Kuipers decided to build a digital marimba with some very unique features that make it more accessible to a drummer.
Called The Marimbatron, this digital marimba has an isomorphic key layout. This layout, also called "Wicki-Hayden," keeps the same shapes for musical patterns, no matter what note you start from. This arrangement makes playing chords and scales easier. For example, if you learn the hand shape for a major chord, you can use that exact shape starting from any key, and it will still play a major chord. Using the traditional piano-like layout, one must memorize different finger positions for different starting notes.
The Marimbatron is built on top of a custom, CNC-machined table. The laser-cut body contains 76 pressure-sensitive pads that take the place of the bars on a traditional marimba, and a sustain pedal can be used to create additional effects. Processing of the inputs is handled by a set of four SAMD21J18 microcontrollers and a single SAMD21E18 serving as the main microcontroller. The instrument is very fast and accurate, allowing it to send MIDI data to a computer in less than 10 milliseconds.
The source code and design files have been made available for non-commercial use, so go grab them if you would like to build your own Marimbatron. And if you happen to be a whiz with the piano and still want a digital marimba, the instrument can be reconfigured with a traditional piano-like key layout.