Info from creator at KrazyDad.com:
In this movie, each of the 48 dots is moving in a circle. Each of the dots is on a 3 minute cycle. At the end of 3 minutes, the outermost dot will have moved around the circle once (this dot represents the first harmonic or fundamental). The next dot will have moved around the circle twice (representing the second harmonic). The next dot three times, and so on. The innermost dot moves around the circle 48 times.
Now, imagine these dots are raised bumps on a disc which is controlling a music box, with each bump triggering a note when it passes the zero degree line (a line extending from the center to the east). The result would look and sound something like this three minute looping movie, which I built in Flash: