(4.5)  Melodic Minor Scale

We have seen two minor scales so far - the Natural Minor, which is a mode of the Major scale, and the Harmonic Minor, which has a distinctly different pattern of intervals.

The distinctive sound of the Harmonic Minor comes from the three semitone interval between the sixth and seventh notes.  For melodies, this large step can be awkward, so another minor scale - the Melodic Minor - evolved as an alternative.

The Harmonic and Melodic Minor scales are similar, except the Melodic Minor contains a natural sixth instead of the flat sixth of the Harmonic Minor.

The Melodic Minor scale is also similar to the Major scale (although still with a distinctly different pattern of intervals).  The only difference is whether the third note makes a minor or major interval.

In classical music theory, the Melodic Minor has a very unusual property, not found in any other scale type.

The intervals as shown above are used when the scale (or a melody made from it) is ascending.  However for descending notes, the intervals of the Natural Minor scale are used instead.

This may strike you as strange (and it is!) but the resulting sound does seem to work in practice.

One of the best examples is the folk tune Greensleeves, shown below in the key of A Melodic Minor.  There is great ambiguity between the notes F/F♯ and G/G♯, which can be more or less freely substituted for each other.

In jazz music theory, and when working out the related chords, this descending form of the Melodic Minor scale is ignored, and it is treated like any other scale, using the intervals listed above.