The chromatic or diatonic scale, contrasted with the tonic or equal tempered scale, is a musical scale consisting of 17 notes, where each sharp and each flat differ by approximately 8hz. It is not well known, as most musical instruments are constructed to use the equal tempered scale for ease of use.
My above definition is also very wrong. *grin sheepishly* A chromatic scale is only segmented by 8hz between middle C and its peers... it actually doubles for every octave upwards, and halves for every octave downwards. I knew this, but wasn't particularly smart when I wrote it, and forgot. ;-) Forgive me.