Grain Kalimba

Documentation & Building Process

  • Material

    The Kalimba was CNC carved out of this block of walnut.

  • CNC Carving

    cnc carving two pieces, top and bottom out of the wood.

  • bottom side

    trying to fit in the first buttons and switches.

  • finish

    the kalimba is oiled with a mixture of natural bee wax and orange oil

  • top side

  • electronics top

    all the controls (buttons, joystick…) are controlled by a teensy microcontroller which sends the data to the main board, a raspberry pi

  • electronics bottom

    a raspberry pi zero with a audio sound card on top and a power supply is mounted on the bottom half of the kalimba.


The raspberry pi runs a pure data patch. It is an effect based on the mutable instruments clouds module which uses code kindly open sourced by mutable instruments and compiled for Linux by „thetechnobear“.

„Grain Kalimba“ is a granular audio processor. It creates textures and soundscapes by combining multiple overlapping, delayed, transposed and enveloped segments of sound taken from an audio recording buffer.

  • Pitch

    Pitch the grains with the joystick up or down.

  • Size

    Grain size/length controlled horizontally with the joystick.

  • Density

    When the joystick is centered, no grains are generated. Turn right and grains will be sown randomly, turn left and they will be played at a constant rate. The further you turn, the higher the overlap between grains.

  • Feedback

    Feedback amount of the grains, controlled vertical with the joystick.

  • Freeze

    This latching button stops the recording of incoming audio. Granularization is now performed on the last few seconds of audio kept in memory in the module.

  • Position

    Selects from which part of the recording buffer the audio grains are played. Turn the knob clockwise to travel back in time.

Advanced controls with the LED-encoder

  • Reverb (blue)

    Controls how much reverberation the effect signal contains.

  • Texture (yellow)

    Morphs through various shapes of 7 grain envelopes: square, triangle, Hann window. Past 2 o’clock, activates a diffuser which smears transients.

  • spread (pink)

    stereo spread / random panning

© 2022 • jonny kölbl