La Guitare à Crayon

The “Guitare à crayon” is a custom instrument for painting and playing music.

The idea behind “la Guitare à crayon” is to be able to paint and play music with the same instrument. It’s a custom USB guitar with open source software: namely, pure data (sound) and gimp (visual).

La Guitare à crayon is free hardware (as in “free speech” not “free beer”).


Hardware features:

  • Accelerometer X-Axis (for example controlling the octave)
  • Accelerometer Y-Axis (for example controlling an effect)
  • 6 analog strings giving around 10 bits of resolution
  • External input: 1 analog, 1 digital
  • 4 positions switch
  • 8 buttons
  • 4 pots
  • 1 piezo with velocity filter (for example trigging any sound)
  • 1 ir distance sensor (+-6cm – +-20cm)
  • 1 unuseful led (for tapping the bpm)
  • Pressure-sensitive tablet
  • Foot controller (using a led & a photoresistor)
  • Foot switch (looper, change sound, …)

Software features:

  • No driver (firmware & bootloader)
  • Linux, Windows, Mac
  • Pure Data poweful DSP (sample, soundfont, fx rack, multiple looper)
  • Gimp for 2d (drawing, painting, photo, …)
  • Gesture tracking on the tablet (linux only)

Work in progress:

  • Converting an electric guitar to an electronic guitar
  • Updating the firmware via http
  • Bridge to Blender (3d)

via Hackaday

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