This is the Grand Staff as it is displayed in Music Theory 101

At first glance you may say, "So what, I've seen that before.", but it is unlikely you have seen it with the corresponding colors in the light spectrum.

Realize that the Grand Staff divides the sound spectrum into intervals, and just as different frequencies in the light spectrum are perceived as different colors, the same is true in the sound spectrum.

The sound spectrum is continuous with the rest of the EM Spectrum.

And as you can see by over laying a piano keyboard and a light spectrum the graduation of light and sound correspond.

Please read more about Synesthesia at WikiPedia.com

http://en.wikipedia.org/wiki/Visual_music