Chromatic harmonica Chromatic harmonica The chromatic harmonica is a type of harmonica that uses a button-activated sliding bar to redirect air from the hole in the mouthpiece to the selected reed-plate desired. When the button is not pressed, an altered diatonic major scale of the key of the harmonica is available, while depressing the button accesses the same scale a semitone higher in each hole. Thus, the instrument is capable of playing the 12 notes of the Western chromatic scale. The chromatic harmonica can thus be contrasted with a standard harmonica, which can play only the notes in a given musical key.
Diatonic scale Pythagorean tuning: Six of the "fifth" intervals (C–G, D–A, E–B, F–C', G–D', A–E') are all = 1.5, but B–F' is the discordant tritone, here ≈ 1.423828125. Extending the series of fifths to eleven fifths would result into the Pythagorean Chromatic scale. It would add pitches for the five "piano black key" notes, for instance A–E–B–F–C–G–D–A–E–B–F–C–G. A and G are commonly thought of as being the same note, but as worked out in this way, G is higher pitch than A by about 1.01364 (, the Pythagorean comma, about 24% of a semitone, = ). Depending on whether one chooses A