subject: When To Use The Harmonic Minor Scale On Guitar [print this page] There are four different kinds of minor scales, each having different characteristics. One of the coolest sounding is the harmonic minor. Guitarists everywhere use this scale, but it's sometimes hard for a beginner to know when the appropriate time is. Let's make it easy.
Let's start first with the A natural minor scale: A B C D E F G A
The Harmonic Minor makes one small change to the natural minor by sharping the 7th scale degree: A B C D E F G# A
Play through both of those scales on your guitar and see if you can hear the difference. The natural minor has a smooth flow all the way to the top of the scale. The harmonic minor has a surprising jump near the end between that F and G#.
Having that combination of two half steps, E/F and G#/A, with the interval of a minor 3rd in between is what gives the harmonic minor its distinctive sound. That means when you want to really bring out the "harmonic minor-ness" of in your guitar solo, those are the notes you want to highlight.
Now let's take a look at the chords that result from each scale. This is going to show us the way to when to use the scale.
A Natural Minor: Am Bdim C Dm Em F G Am
A Harmonic Minor Am Bdim Caug Dm E F G#dim Am
When you change one note in the scale, it affects at least 3 of the chords because that note can be the root, 3rd, or 5th of the chord. And if you take them out to 7th chords, it would affect one more. In this case Am7 would become Am(maj7).
Once you know what key you're in, look to see if any of those altered chords are present in your chord progression. You're looking for the Augmented III chord, the Major V, or the Diminished VII. The most common will be the Major V. Wherever you see those chords, that's where you want to use your harmonic minor scale.
Let's look at an example guitar chord progression:
Am G Dm E7 Am Caug G#dim Am
Question #1: Could you solo with the harmonic minor scale over this whole progression?
Answer: No, only part of it.
Question #2: Which chord doesn't fit with the harmonic minor?
Answer: The G major (2nd chord). The G# in your scale will clash with the G natural in the chord.
Question #3: At what point in the progression is it appropriate to start using the harmonic minor?
Answer: When you get to E7 you definitely want to use it. Though you can use it over the Dm as well.
For the first three chords, you're in the key of A natural minor as evidenced by the G major chord. Once you hit the E7, you're definitely in the harmonic minor and all the chords after that reflect it. In this case you can't just pick one scale and stay there. You have to change scales based on the chords. This is one of the things that can make soloing in minor keys more challenging that major keys.
You can start using the harmonic minor over the Dm chord, but it's almost like telegraphing the change of tonality before you get there. It ruins part of the surprise for your listener.
Bottom Line: Look at your chord progression and find the chords that belong to the harmonic minor scale (Aug III, Major V, and Diminished VII) and use the harmonic minor over those chords. For the other chords you can use either the natural or harmonic, depending on your mood.
