I am working on a student project demonstrating basic Arduino literacy.
I want to rig up a guitar with six sensors, one for each string. Under the sound hole, I want to place a neopixel ring. Then I want to do some basic programing so that the light will be different depending on what note or combination of notes are being played.
I do not want to measure frequency or sound or pitch... I just want Arduino to respond to whether or not a note is being played.
I would love any general advice, but especially what type of sensor can best accomplish this.