Basics of the Harmonic Minor Scale on the Guitar
Before you dive into the harmonic minor scale on the guitar, you need to understand the concept of dominant function. Basically, dominant function is the tendency of the dominant chord, chord V, to pull to the tonic, chord I, in a key. Similarly, secondary dominants are a way of using the dominant sound to strengthen a progression toward chords other than the tonic.
Some examples include II7 leading to V, VI7 leading to ii, and III7 leading to vi. In the latter example, III7 leading to vi creates the harmonic minor scale. In order to change what is normally a minor iii chord to a major III chord, the 7th note of the relative minor scale is raised.
III7-vi is a very important chord change in music because it uses dominant function to lead to the relative minor — one of the most common types of keys. Because musicians prefer to think of the relative minor tonic as “1,” you can also think of III7-vi as V7-i in the relative minor key with the major V chord a result of the harmonic minor scale.
How to raise to the 7th scale degree on the guitar
One way to think of the harmonic minor scale is as an altered version of the natural minor with its 7th scale degree raised by a half step. For example, when you play an A minor scale and raise the 7th G to Gs, you’re playing an A harmonic minor scale:
A Natural Minor
A Harmonic Minor
The chords of the A minor scale are the same as its relative major, C, except that they start on Am:
When you renumber these chords with A as the tonic, you get the following sequence:
Notice that the dominant chord (the chord built on the 5th scale degree named the dominant) is minor. In A, it’s an Em chord: E, G, and B.
Take a look at how the raised 7th of the harmonic minor scale affects the dominant chord. In A harmonic minor, the 7th scale degree is raised from G to Gs. This Gs changes the Em chord, E-G-B, to E major, E-Gs-B. The v chord becomes V, making a much stronger dominant-tonic V-i chord progression.
As with major keys, you can add a 7th (creating a dominant 7th chord) to intensify the movement from dominant to tonic. In our A minor example, this would be E7-Am. Songs in minor keys often use V7 chords.
If you’re a soloist, keep in mind that you only need to use the harmonic minor scale temporarily. Typically, you use the natural minor scale until the dominant chord sounds, at which point you need the raised 7th of the harmonic minor. In other words, when the V or V7 chord appears, use the harmonic minor; for all other chords, use the natural minor.
How to identify harmonic minor chord progressions on the guitar
Here are several examples of typical harmonic minor chord progressions. Notice that the progressions use chords from the A natural minor scale, except for the V7 chord, E7, which comes from the harmonic minor scale.
Here is an Am-E7 harmonic minor chord progression. Something similar is used in “Istanbul (Not Constantinople)” by Santo & Johnny.
You can play-along to a backing track of this in A Harmonic Minor Play-Along Track.
Here is an Am-Dm-E7-Am harmonic minor chord progression. Some of the same chords are used in “Abracadabra” by Steve Miller Band.
Here is an Am-F-E7 harmonic minor chord progression. The main sections to “Smooth” by Santana are based on a nearly identical progression.
Here is an Am-G-F-E7 harmonic minor chord progression. “Walk, Don’t Run” by The Ventures starts out with the same chord changes.
Here is an Am-Dm-G-C-F-Bm7f5-E7 harmonic minor chord progression. Some songs based on similar chord movement include “El Farol” by Santana, “I Will Survive” by Gloria Gaynor, and “Still Got the Blues” by Gary Moore.
You can play in other harmonic minor keys simply by playing a minor chord and a dominant 7th chord a 5th above it; for example, Em and B7, Fm and C7, Dm and A7, and so on.