I went a step further and bought 20 extension cables from China for ~$2 each. I snipped off the “wrong” end of the cable with about six inches of wire (in case I wanted to make a control someday).

DIY Arduino Hearing Test Device. 18 Comments . by: ... By using an Arduino to produce tones of various stepped frequencies, ... and a rotary encoder with push-button serves as the user input.

If you are looking for a project to keep you busy this weekend you might be interested in a new MIDI fader unit which is being created using a little 3D printing and Arduino programming. Check out ...