What are the different types of diatonic harmonica?
First of all, let’s define “diatonic” To put it simply, the term diatonic refers to a selection of notes having no sharps or flats other than those prescribed by the key signature. For example, something that is diatonic to C major has the notes C, D, E, F, G, A and B, but no sharps or flats; something that is diatonic to C# major has the notes C#, D#, E#, F#, G#, A# and B#, but no flats or naturals; and so on. In the case of the harmonica, it usually means that the instrument’s layout has the notes of a particular major scale, some of which may be omitted and/or repeated, but has no notes from outside of that scale. For almost a century after it was invented, the harmonica was nearly always a diatonic instrument and several varieties of the diatonic harmonica evolved over the years.
