This listens to your computer’s microphone and draws the contents of the audio buffer as a series of ellipses that are rotated based upon the audio sample’s position in the buffer. The difference between this one and v1 is that v1 has a sort of threshold so that it only shows values above a certain level. To compensate, the line on v2 is 1/10 the width.
This was made as part of a series exploring the visualization of audio that was presented at a d3.oakland. A big list of the demos from this series can be found here.