Ryan York composed the sounds you're hearing.
It seems like sometimes one sense can be focused by ignoring others. Close your eyes when listening. This project is trying to do something like the opposite of that; revealing nuances in both the sound and graphic which you'd have a hard time realizing if it weren't for both played in conjunction.
Sound frequencies are mapped linearly over time from low (bottom) to high (top), while brightness is determined by amplitude. Sweeping tones and rhythmic patterns create intricate structures. The circular form is in memorial of dead formats; the CD,
Lee Martin, a developer at Soundcloud, built a generative incarnation with canvas and the SoundCloud API, located at spectrogr.am. You should take a look at what Lee did. It's very similar to what was in mind when compositing this video, and you gain a better sense of what is happening by plugging multiple tracks in.
Andrew Ohlman, a friend also with Cargo, compiled a Quartz sketch which does similar things.
