LIVE from the Lab: Arduino NANO Midi Controller - YouTube
Turn an Arduino Uno into a MIDI Controller: Guitar Pedals - Arduino Project Hub
10 MIDI Controllers You Can Build With an Arduino
Building a Basic Midi Controller Part 1 - Easy 3 Pot (Potentiometer) Arduino Uno Effects Midi Controller (Serial-USB)... Quick,easy and Cheap! : 7 Steps (with Pictures) - Instructables