The visible part of the electromagnetic spectrum is represented by less than an octave of the keys; UV, IR, and microwaves are also indicated.
What it shows:
The keys of a piano are used to represent the electromagnetic spectrum, illustrating the narrow range of frequencies that constitute the portion visible to human sight.
How it works:
An old piano 1 with its center octave of keys (C4=261.6Hz to C5=523.3Hz) colored for the visible spectrum (the seven colors spread to...
Read more about Spectrum Piano