OOBOX Instrument Tuner v2.0. Guitar Tuner! OOBOX Instrument Tuner V2.0 can help you to tune your instrument - By ear If your computer can play MIDI Sounds, OOBOX Tuner will play one sound for each string, you just have to reproduce the same sound on your instrument. - Using the digital tuner. If your computer can record the sound of your guitar (with a microphone or a direct cable), OOBOX Tuner can show you graphically the distance between the good note and the note you are playing : just adjust the needle !