Harmonic minor scale

The harmonic minor scale is so called because in tonal music of the “common


practice period” (from approximately 1600 to approximately 1900) chords or


harmonies are more commonly derived from it than from either the natural minor


scale or the melodic minor scale. The augmented second between its sixth degree


and its raised (“leading tone”) seventh degree, usually traditionally considered


undesirable, is easily avoided by distributing these pitches among voices. In the


chord progression, D F A(flat), B F G, C E(flat) G, (ii0, V7, i in C minor) for example,


the Ab in the upper voice never ascends to B, and the B in the lower voice never


descends to Ab.