Chromatic harmonicas are designed to play every complete scale in any key. Each single hole contains four reeds: two natural notes and two chromatic notes. The reeds for chromatic notes are enabled by pushing the slide button on the side of the harmonica. This design offers a wealth of new musical options to the player. Most often, chromatic harmonicas are heard within the classical and jazz scenes, but...chromatics are frequently found in blues, folk, rock and pop music. The 64 Chromonica is preferred by professionals and semi-professionals for it's excellent reed response and bright tone over all four octaves. It features an extra octave in the lower register (below middle C), which makes it possible to play advanced repertoire.