A basic Arduino-based MIDI controller that uses pots and buttons to send MIDI. Works with any Atmega32u4-based Arduino (Leonardo, Micro, Pro Micro, Lilypad USB), and uses the USB port connect to the computer, using the MIDIUSB library.

• Atmega32u4-based Arduino (Leonardo, Micro, Pro Micro, Lilypad USB)
• Potentiometers (~10k, but anything between 5k and 50k should work)
• Some filter capacitors (~1µf give or take an order of magnitude) if your pots are noisy.
• Buttons (momentary switches)
• A case, if you want
• some way of getting a USB connection from your computer to the Arduino.

• Hook the pots up (1: ground, 2 (wiper): analogue pin, 3: +5V)
• Add a filter cap from ground to wiper for each potentiometer (pin 1 to 2), if you're getting noise on the pots.
• Adjust the pin values as appropriate in the code and upload the sketch, and you should be good to go.