MIDIKnob is a compact yet powerful programmable encoder controller designed for both MIDI control and everyday system interaction.

The device supports multiple operating modes, selectable via the switch on the right side:

• MIDI Mode
• System Volume / Keyboard Shortcut Mode

For each mode, a switch on the left allows you to select one of three stored presets, giving you instant access to multiple configurations.

In MIDI mode, MIDIKnob Basic sends a MIDI CC message on the assigned controller number while the encoder is rotated. Pressing the encoder sends a Note On / Note Off message.

The device also responds to incoming MIDI Clock, pulsing the encoder’s LED on the start of each bar and on every beat—providing clear visual timing feedback.

Programming MIDI behavior is quick and intuitive: simply double-tap the encoder and send a MIDI CC or Note On message. The assignment is saved to non-volatile memory and recalled automatically on power-up.

System Volume / Keyboard Mode In System Volume mode, the device operates as a USB HID controller, allowing native control of your computer’s audio volume. Rotating the encoder adjusts volume up or down, while pressing the encoder sends a default keyboard command, which can be remapped as needed.

Hardware & Firmware: MIDIKnob is built around a Raspberry Pi RP2040 mini shield and features a USB-C. Also includes TRS-A MIDI out in XL model. The firmware runs on CircuitPython, and the full source code is available on GitHub under the BSD-3 license. Modifications and customizations are fully encouraged.

Dimensions:

• MIDIKnob XL 50x50, aluminum enclosure
• MIDIKnob Value/Basic 48x34, plastic enclosure

Purchasing Options:

• Complete kit - includes PCBs, all required components, RP2040 controller. For XL model the aluminum case comes pre-drilled and raw (not painted). For Value/Basic plastic case needs holes.

• Assembled unit - has all components soldered, for XL aluminum case sprayed in black and device is programmed with basic firmware. Comes with USB-C/USB-C cable.

Differences between MIDIKnob Value, Basic, XL:

• MIDIKnob Value - plastic case, standard encoder with push button, one switch (mode change), RGB LED on the side
• MIDIKnob Basic - plastic case, bi-color encoder with transparent plastic cap and push button, two switches (mode change + 3-pos preset), RGB LED on the side
• MIDIKnob XL - painted aluminum case, bi-color encoder with transparent black anodized aluminum cap and push button, two switches (mode change + 2-pos preset), RGB LED on the side, hardware MIDI TRS-A output

Design notes:

• Beginner soldering skills required. That means you have to understand schematics, not just being able to solder two wires together. There are no high expectations, but being able to read schematics and understand polarity of components are quite important.
• For DIY kit you need to paint aluminum case (XL model) or make holes in plastic case (Value/Basic).

Please, consider Deftaudio page at Github for additional information.