Philip Galanter

This video is also projected on a full wall, and is carefully adjusted to make the "bubbles" appear to be moving freely.

There are two sets of bubbles, one set moving from top to bottom, and one set moving from bottom to top. As a bubble enters the screen (i.e. the wall) it makes a unique sound where the pitch is related to the bubble's color. There are 2 sets of pitches which are harmonically related. Colors closer to primary colors result in a sound from one pitch set, and those closer to secondary colors result in a sound from the other pitch set.

There is a color wheel that determines the three complementary colors used by a set of bubbles at any time. Each bubble corresponds to one of three corners of a triangle slowly rotating within the color wheel. Bubbles are randomly assigned a corner, but some corners are more heavily weighted than others. The bubbles are actually slowly changing color due to rotation within the color wheel.

Bubbles are randomly assigned a right-to-left position as well as a velocity. Because the two sets of bubbles have their own color wheels that rotate at a different speed, the varying phase relationships result in ever changing color and harmony relationships.