by 17bhuey @ instructables.com:
In order to create this project, many physical materials are necessary, a lot of which will not be found lying around at home. In order to do this project, you should go out to computer stores or look online for these products. Keep in mind that you can upgrade to larger LED boards or faster arduinos, but that would require some modification of this tutorial as the coding, wiring, etc, changes with the addition of different products. Overall, this project is a fun way for you to practice your engineering, circuitry, and computer science skills while making a device that shows off your music taste in a new light.
LED Wave Display – [Link]