Our project is composed of three main components:

The 1.) EMG amplifier, 2.) the Arduino, and 3.) the MIDI device.

1. We'll build the EMG amplifier on a breadboard. If you're interested in a more in-depth look at the science behind the EMG amplifier and more detailed steps on how to build your own, check out my EMG audio amplifier Instructable.
2. We'll power the Arduino from the same 9V batteries that power the EMG amp. Most of the work with the Arduino will be on the software side.
3. I used an iPhone running Garageband as my MIDI device. The Arduino will send standard MIDI signals over a standard MIDI cable, so any MIDI device should work in place of the iPhone.

Parts

• (2x) LT1167 (instrumentation amplifier)
• (2x) LT1112 (or any dual op-amp chip)
• (1x) LM386N (audio amplifier)
• (5x) Surface EMG electrodes (two per muscle and one for a reference) (Amazon)
• Arduino Uno (Amazon)
• iPhone (or any MIDI device)
  • MIDI to iPhone adapter cable (if using an iPhone) (Amazon)
• Various resistors, capacitors, and jumper wires
• Breadboard (Amazon)
• (2x) 9V battery

Tools

• Soldering iron (Amazon)
• Wire strippers
• Heat shrink tubing
• Electrical tape