Switchback is a headless double-neck guitar with a keyboard for playing neurometal. It can integrate with a sequencer to perform a software synth and display the waveform in an onboard oscilloscope built into the handle.

For this project my goal was to get into electrical engineering, learn embedded development on Arduino, display graphics on a screen with the SPI protocol, and process audio from a bluetooth receiver.

• 6-string (bottom) modeled after Strandberg Boden Metal 6 with Fishman Fluence Modern 6 pickups
• 8-string (top) modeled after Strandberg Boden Metal 8 with Fishman Fluence Modern 8 pickups
• 9-key Roli Seaboard Block keyboard (bottom) with two extra dimensions of touch is trimmed into a custom shape and embedded into the body
• Built-in oscilloscope can display a waveform from a remote synth or sampler, for an effect similar to Korg Minilogue

To embed a Seaboard MIDI controller in the guitar body, I started by separating the keyboard surface from the case with ribbons and adapters. Then I re-cast the surface in Ecoflex 50 so it could be re-skinned without affecting function.

The source code for the built-in oscilloscope that analyzes audio signals and displays waveforms is available on GitHub:

Clone the GitHub repository to download CAD models and building instructions.