Now that we have talked about both the natural minor and harmonic minor scales, lets take a minute to introduce the 3rd minor scale in our repertoire: the melodic minor scale. The Melodic Minor scale, in traditional application, has a different formula when ascending and when descending. When ascending, the melodic minor’s formula is: 1 2 b3 4 5 6 7, and when descending, the melodic minor’s formula is the same as the natural minor’s formula: 7 b6 5 4 b3 2 1.
Essentially, the melodic minor is a combination of the minor scale and the major scale, much more so than the harmonic minor scale. Where the harmonic minor retains the b6 (flat 6) of the natural minor scale, creating the sometimes unwanted, augmented 2nd, the melodic minor takes the 6 from the major scale, fixing this problem (if it is one).
So, the key of A melodic minor will have:
A melodic minor:
Ascending: 1 2 b3 4 5 6 7: A B C D E F# G#
Descending: b7 b6 5 4 b3 2 1: G F E D C B A.
And here is the harmonic and natural minor again for comparison:
A harmonic minor:
Ascending and Descending: 1 2 b3 4 5 b6 7: A B C D E F G#.
A natural minor:
Ascending and Descending: 1 2 b3 4 5 b6 b7: A B C D E F G.
One of the easiest mistakes to make is that, for whatever reason, you have to either be in the natural minor scale or the harmonic minor scale, and can’t be in both – or that we have to be in the melodic minor scale the entire time, and never in the harmonic minor scale, for instance.
For some pieces you may want to stick with one scale and its endemic modes/positions, but for most musically intensive compositions, switching scales and modes is not only a common thing to do, it is generally encouraged and might sound a bit odd if you don’t change scales/tonal centers over the course of a piece.
For most rock and popular music, you won’t switch keys or scales that frequently, but even in more accessible styles of music, a little bit of derivation can go a long way. As an example, applying the natural minor in one verse, and the melodic minor the next time it occurs, can give a song just enough variation to become more interesting, yet not so much that the listener thinks of it as a different section of the song.
One thing that has helped me is to think of scales like we think of chords: often and almost always changing. Just as we get more and more skilled with writing nice chord progressions, we want to get just as skilled with our melodic writing as well. We want to get to a point where we are able to switch scales just as easily and smoothly as we can switch chords.
And in the case of the minor scales, this is even more so: An A minor chord is: A C E, and ALL 3 minor scales (natural, harmonic, and melodic) can work over that chord, depending on the setting. Everytime that chord comes along again in a chord progression, we can apply a different scale for effect, or to accentuate/facilitate the direction the chord progression is headed. For instance, we may be headed to A major from A minor, and when this is occurring, switching to an A melodic minor scale would be very appropriate, as it can be used as a transitory scale between the two parallel modes: A major and A minor.
It’s also important to note that in jazz, the melodic minor is generally only applied in its ascended form, known as the “jazz minor scale”, and in these situations, it would be played the same ascending and descending: 1 2 b3 4 5 6 7 (or a major scale with a b3).
Hopefully this helps to explain the versatility of the melodic minor scale and demonstrates several functions that can be applied across the board when working with any scale or chord progression. Next time we will wrap up our mini-series on music theory by taking a look at chord substitutions and their function within this realm.