The team at New York University have described some interesting methods of creating music with an Arduino and a voltage-controlled oscillator. It's always good to see a mixture of analogue and digital electronics - they're using pulse-width modulation from the Arduino to control an astable oscillator created with a 7555 timer IC. The pitch can then be altered with a potentiometer read by the Arduino and detected by a guitar tuner ... or a well-trained ear! And then the values can be recorded in the sketch to play specific tones.
If you're not too interested in tunes it's still an interesting learning exercise, so click here to get started. And for more, we're on twitter and Google+, so follow us for news and product updates as well.