Melodic Minor Truths I: There Is No Descending Form Of The Melodic Minor (Redux)

This issue came up again recently with a student and so I thought I would bring it to the group once more, as it is vitally important in actually understanding how music, and in particular scales, behave.

Just as the Natural minor is not a scale in its own right but rather it is mode VI of the Major scale, and therefore any music deemed to be in a minor key using the natural minor is actually modal, with the Aeolian mode being the focus of the music, the Melodic scale does not alter its form when it descends.

For those of you that may be unfamiliar with this issue, in classical pedagogy, when a Melodic minor scale is played, ascending and then descending, the traditional thought is that the scale changes from having a Major 6th and 7th to a minor 6th and 7th. So ascending and then descending in C Melodic would be: C D Eb F G A B C Bb Ab G F Eb D C. You can see here the alteration of the B and A on the way back, becoming Bb and Ab.

This was never explained properly in the books, but what is actually happening is that the scale is changing at the point when the octave is reached, C Melodic to C Aeolian. This is because there is an implied cadence occurring, G7 to C minor. Try playing the example below for yourself:

The erroneous belief that the Melodic minor changes form when it descends creates a lot of misunderstandings in music, especially when musicians come to write their own music. A scale never changes its form, it cannot as that is an impossibility. The scale itself changes and the fact that it does means that a change in the music is implied.

This fallacy may have arisen for one reason or another, different schools have different opinions, but the fact of the matter is we no longer need to follow this line of thinking as it is harmful and false. When the Melodic minor is used outside of simple scale repetition, and in the form over an implied V- I minor, it does not behave this way at all, a Melodic minor scale descending but using the notes of the ascending form is commonly found. This is a contradiction and proves that the idea that the scale changes form when descending is completely false. Hopefully, you can pass it on to your students and we can leave this behind, except as an historical oddity.