Hohner 280C 64 Chromonica Harmonica - Key Of CChromonica 64 280 First conceptualized in 1938 and improved in numerous details throughout the 20th century. A top quality 4 octave chromatic for professionals and semi professionals. In addition to the excellent handling, the Chromonica 64 offers fast response in all octaves. The Chromonica 48s big sister features an extra octave in the lower register, which makes it possible to play a more advanced repertoire.