You don’t really have to imagine it, as designers Hideaki Matsui & Momo Miyazaki have done just that with the Audible Colors project. It is an audio-visual instrument where sound is generated based on the color detected by a webcam connected to a computer. Musical notes correspond to certain colors (red, green and blue). And just like the color wheel, when you mix the primary colors, the secondary colors produce different notes. Not sure if there's a practical application in the world of all things EDM culture, but dope none-the-less.
Here’s some more bits and bobs about the project.
The size of the colors influences the volume and frequency of the notes played.
Color detection and sound generation were created and are controlled using Processing code.
The system of audible color is based on a marriage between basic color and music theories.
The colors of red, blue, and green are the visual foundation for color-mixing and the music notes A, D, and F are the base triad that corresponds to the colors.
The secondary colors (colors made when the foundational three are mixed) of purple, teal and brown are tuned to the musical triad C, E and G.
The visual of the mixing of red, blue and/or green mirrors the aural output of combined notes.