Chapter 9:
Minor key harmony
What is a minor key?
Minor keys are the moody counterparts of major keys. In Western music, minor keys tend to be considered sad and dark, and major keys happy and bright, though this is not universal. Minor keys include intervals not explored in major keys, which can lend an air of mystery and sophistication.
Songs in a minor key use notes and chords derived from the natural minor scale, plus an added leading tone and adjustments to the sixth and seventh degrees (see Chapter 17. Minor scales). Like major keys, minor keys are tonical: they place a special emphasis on the first scale degree, the “tonic” or “keycenter”, the note for which the key is named.
Chords in natural minor
Most of the chords in a minor key are determined by harmonizing the natural minor scale. See Chapter 6. Introduction to Western harmony for details.
Notice that in a minor key:
- the i, iv, and v diatonic chords are minor,
- the bIII, bVI, and bVII chords are major, and
- the ii chord is a diminished triad.
| Chord | In Am | Scale degrees | In Am | Chord factors | Chord type |
|---|---|---|---|---|---|
| i | Am | 1-b3-5 | A-C-E | R b3 5 | minor |
| ii° | B° | 2-4-b6 | B-D-F | R b3 b5 | diminished |
| bIII | C | b3-5-b7 | C-E-G | R 3 5 | major |
| iv | Dm | 4-b6-1 | D-F-A | R b3 5 | minor |
| v | Em | 5-b7-2 | E-G-B | R b3 5 | minor |
| bVI | F | b6-1-b3 | F-A-C | R 3 5 | major |
| bVII | G | b7-2-4 | G-B-D | R 3 5 | major |
Relative major and minor
The notes in a natural minor scale are identical to the notes in the relative major scale a minor third above it. For example, the notes and chords in A natural minor are the same as the notes in C major.
This is a quick way to get started learning the chords in a minor key: by learning a major key we get the relative minor for free.
| Minor key (Am) | Chord | Major key (C) | Major degrees | Minor degrees | Notes | Chord factors | Chord type |
|---|---|---|---|---|---|---|---|
| i | Am | vi | 6-1-3 | 1-b3-5 | A-C-E | R b3 5 | minor |
| ii° | B° | vii° | 7-2-4 | 2-4-b6 | B-D-F | R b3 b5 | diminished |
| bIII | C | I | 1-3-5 | b3-5-b7 | C-E-G | R 3 5 | major |
| iv | Dm | ii | 2-4-6 | 4-b6-1 | D-F-A | R b3 5 | minor |
| v | Em | iii | 3-5-7 | 5-b7-2 | E-G-B | R b3 5 | minor |
| bVI | F | IV | 4-6-1 | b6-1-b3 | F-A-C | R 3 5 | major |
| bVII | G | V | 5-7-2 | b7-2-4 | G-B-D | R 3 5 | major |
Though the keys of C major and A minor have the same chords and the same notes, the two keys feel different. The chords in the different keys have a different meaning, a different keycenter, different scale degrees, and different harmonic functions.
Leading tone and harmonic minor
The natural minor scale does not have a leading tone. Its seventh degree is a minor seventh, not a major seventh.
But euroclassical composers used the leading tone in minor key songs anyway, and called it “harmonic minor”. The irresistible pull of the leading tone into the tonic is a seductive harmonic device, and it can sound particularly poignant in a minor key.
Adding the leading tone to natural minor creates some new chords that can be used in cadences: dominant V and diminished vii, just like in a major key.
More specifically, raising the b7̂ degree of the scale changes the v chord from minor v to major V (or V7), and changes the bVII chord from major bVII to diminished vii°. These are the same dominant V and diminished vii degrees as in a major key, enabling all the same cadences and tricks of harmonic function.
| Chord | In Am | Scale degrees | In Am | Chord factors | Chord type |
|---|---|---|---|---|---|
| v | Em | 5-b7-2 | E-G-B | R b3 5 | minor |
| V | E | 5-7-2 | E-G#-B | R 3 5 | major |
| V7 | E7 | 5-7-2-4 | E-G#-B-D | R 3 5 b7 | dominant 7 |
| bVII | G | b7-2-4 | G-B-D | R 3 5 | major |
| vii° | G#° | 7-2-4 | G#-B-D | R b3 b5 | diminished |
It is common to mix both 7̂ and b7̂ degrees freely in the same minor key composition. The chords minor v and dominant V7 might be used in the same song, and the bIII is usually played as a major triad (with the b7̂, rarely as an augmented triad with the leading tone.)
Additionally, euroclassical composers preferred to avoid melodic leaps around the leading tone, and so adjusted the intervals of the sixth and seventh scale degrees in melodic lines according to taste. These contortions are collectively called “melodic minor”. (See Chapter 17. Minor scales).
C shape i chord position
Compare these diatonic minor chords around a C shape i chord with their relative diatonic major chords in D shape I position.
Minor key chords in C shape i position
Practicing these chords
Play minor key songs in position
One of the most effective ways to practice is to play minor key songs we already know using chords in a single position.
Think in relative major with a dominant III
When first working with a minor key, it can be easiest to think in terms of a relative major key we are already familiar with. If we know the chords in C major, we can play in the key of Am while thinking of the C major chords.
To make it feel more like the minor key and less like the relative major, hang out around the vi (Am) to make it feel like home. Play III-vi cadences to help establish vi as the tonic (E-Am or E7-Am). Use the leading tone a semitone below the 6̂ (G#-A) in melody lines.
Think in primary and secondary chords
The primary chords in a minor key are the same as the secondary chords in its relative major, and vice versa.
| Primary chords | Secondary chords | |
| Minor key | i, iv, v (Am, Dm, Em) | bIII, bVI, bVII (C, F, G) |
| Major key | I, IV, V (C, F, G) | vi, ii, iii (Am, Dm, Em) |
This example practice loop combines primary and secondary chords with cadences from relative major and minor scales, and transitions of descending fifths. It’s a way to practice the relative major and minor keys at the same time.
I-IV-I-V (C-F-C-G)
I-V-vii°-I (C-G-B°-C)
IV-vii°-iii-vi (F-B°-Em-Am) (bridge)
vi-ii-vi-iii (Am-Dm-Am-Em)
vi-iii-III-vi (Am-Em-EM-Am)
ii-V… (Dm-G…) (turnaround)
(repeat)
Think in minor with a leading tone
Once some familiarity with the chords is developed, start to practice them while thinking of the i minor chord as the tonic, and all chords and scale degrees oriented toward that.
Use the leading tone in cadences with dominant V and diminished vii movements to the tonic to establish the minor feel.
It can be constructive to try flipping perspectives back and forth, thinking of a chord in context of both the minor and relative major scales.
A shape i chord position
Compare these diatonic minor chords around an A shape i chord with their relative diatonic major chords in C shape I position.
Minor key chords in A shape i position
G shape i chord position
Compare these diatonic minor chords around a G shape i chord with their relative diatonic major chords in A shape I position.
Minor key chords in G shape i position
E shape i chord position
Compare these diatonic minor chords around an E shape i chord with their relative diatonic major chords in G shape I position.
Minor key chords in E shape i position
D shape i chord position
Compare these diatonic minor chords around an D shape i chord with their relative diatonic major chords in E shape I position.
Minor key chords in D shape i position
Shapes on the whole fretboard
