Module 2: Theory ILesson 4beginner⏱ 75 min + two weeks of drills

The three minor scales

Natural, harmonic and melodic minor: their formulas and spellings, relative versus parallel minor, a fingering for each, and which one jazz players actually use where.

Why there are three

Minor keys have a problem that major keys do not. The major scale has a half step between its 7th degree and the root, and that leading tone is what makes the V chord pull so strongly home. The natural minor scale has a whole step there, so its V chord is minor and the pull is weak. Classical and jazz musicians solved this centuries ago by raising the 7th, which created the harmonic minor scale, and then smoothed out the awkward gap that raising it leaves by also raising the 6th, which created the melodic minor scale. The result is three minor scales that share the first five notes and differ only in their 6th and 7th degrees.

In jazz you will use all three, but not equally, and not in the way classical theory books describe. Knowing which one fits which chord is the practical goal of this lesson.

Natural minor: the relative-minor scale

Natural minor is the major scale started from its 6th degree, so it is the scale of every relative minor key from the key-signature lesson. Measured against the major scale on the same root, its formula is 1 2 b3 4 5 b6 b7: three notes are lowered. Its other name is the Aeolian mode, which is how the scale finder and later lessons on modes refer to it.

The table shows all three minor scales from A, which is the easiest minor key to think in because A natural minor has no sharps or flats (it is the relative minor of C).

Here is one octave of A natural minor with the root on the 6th string at the 5th fret, up and down. Note the step pattern: W H W W H W W, which is the major-scale pattern started from its sixth step.

\tempo 84
.
\ts 4 4
:8 5.6 7.6 8.6 5.5 7.5 8.5 5.4 7.4 | 7.4 5.4 8.5 7.5 5.5 8.6 7.6 5.6 |

Where you use it: over a minor chord that is functioning as the vi chord of a major key, and over long stretches of a minor key where the harmony is static. It gives the plain, folk-like minor sound, with the b6 as its characteristic note.

Harmonic minor: the raised 7th

Raise the 7th degree of natural minor by one semitone and you have harmonic minor: 1 2 b3 4 5 b6 7. The name tells you its purpose: it exists to supply the harmony of a minor key with a leading tone, which turns the V chord from minor into a dominant 7th that pulls home.

The price is the gap between the b6 and the 7: an augmented 2nd, three frets, which sounds exotic and is hard to sing. Play it and you will hear why melodies tend to avoid it.

\tempo 84
.
\ts 4 4
:8 5.6 7.6 8.6 5.5 7.5 8.5 6.4 7.4 | 7.4 6.4 8.5 7.5 5.5 8.6 7.6 5.6 |

Where you use it in jazz: on the V7 chord of a minor key, which is where the raised 7th lives. The scale's b6 sits a half step above the 5th of the V chord and gives that chord its characteristic b9 colour. Here is an original two-bar phrase over E7 resolving to Am, built entirely from A harmonic minor; notice how the G# on the E7 falls naturally to A.

\tempo 112
.
\ts 4 4
:8 7.5{ch "E7"} 6.4 7.4 8.5 7.5 6.4 5.3 7.3 | 7.4{ch "Am"} 5.3 7.3 5.2 7.4.2 |

A spelling note: the raised 7th keeps its letter. In A minor it is G#, not Ab; in C minor it is B, not Cb; in Eb minor it is D. The scale therefore mixes flats and a natural, or flats and a sharp, and that is correct for minor scales, unlike the major scale.

Melodic minor: the jazz minor

Raise the 6th as well and the gap disappears: melodic minor is 1 2 b3 4 5 6 7, which is simply a major scale with a lowered 3rd. Classical textbooks teach it with the raised 6th and 7th going up and the natural-minor notes coming down. Jazz does not do that. Jazz musicians use the raised form in both directions, and to make the distinction clear they often call it the jazz minor scale. Whenever this course says melodic minor, it means the same notes ascending and descending.

\tempo 84
.
\ts 4 4
:8 5.6 7.6 8.6 5.5 7.5 9.5 6.4 7.4 | 7.4 6.4 9.5 7.5 5.5 8.6 7.6 5.6 |

Where you use it: on the tonic minor chord of a minor key when it is played as a minor-major 7th or minor 6th chord (the sound of a minor tune's final chord), and, more importantly, its modes supply the scales for altered dominants and half-diminished chords, which is why it gets a whole lesson of its own in the scales and modes module. For now, learn it as a sound: bright on top, dark at the bottom. The original phrase below sits over an AmMaj7 chord and uses only A melodic minor.

\tempo 120
.
\ts 4 4
:8 7.4{ch "AmMaj7"} 5.3 9.3 9.2 10.2 9.2 7.2 9.3 | 7.3{ch "AmMaj7"} 5.3 9.4 6.4 7.4.2 |

Relative versus parallel

Two words you need to keep apart:

• The relative minor of a major key shares its key signature and starts on the major scale's 6th degree: C major and A minor.
• The parallel minor of a major key shares its root: C major and C minor. The parallel minor has a different key signature (three more flats, or three fewer sharps).

Jazz uses both relationships. Many standards slide between a major key and its relative minor, so a chorus "in C" will spend bars in A minor. Many others borrow chords from the parallel minor to darken a major key; a minor iv chord in a major tune comes from that relationship, as the harmony modules explain. For practice the parallel approach is the useful one: all three minor scales from the same root (as in the three one-octave examples above) teach you exactly which notes change.

A two-octave fingering

The one-octave shapes above are for learning the sound. For playing you need a position fingering. Here is G melodic minor with the root on the 6th string at the 3rd fret, two octaves in one position. Because G minor has two flats (its relative major is Bb), the raised 6th is E natural and the raised 7th is F#.

\tempo 88
.
\ts 4 4
:8 3.6 5.6 6.6 3.5 5.5 7.5 4.4 5.4 | 7.4 3.3 5.3 7.3 5.2 7.2 8.2 r | 8.2 7.2 5.2 7.3 5.3 3.3 7.4 5.4 | 4.4 7.5 5.5 3.5 6.6 5.6 3.6.4 |

To get G harmonic minor from this fingering, lower every 6th degree (the E naturals) by one fret. To get G natural minor, lower the 7th degrees (F#) as well. Practising the three scales as alterations of one fingering is far faster than learning three unrelated shapes, and it trains you to hear what the raised notes do.

Which minor scale, where: the short version

• Natural minor (Aeolian): vi chords in a major key; minor vamps where the b6 is wanted; the plain relative-minor sound.
• Harmonic minor: the V7 chord in a minor key, especially V7b9; minor-key cadences.
• Melodic (jazz) minor: tonic minor chords written as m6 or mMaj7; and, through its modes, altered dominants and half-diminished chords (later module).

A very common real-world case: a minor ii–V–i. Players will typically use harmonic minor (or just its arpeggio) over the V7 and switch to melodic minor on the i chord, which gives both the leading tone at the cadence and a bright, resolved tonic. You will build that progression in the next module; the scales are ready now.

Exercises

1. Three in a row. From one root, play natural, harmonic and melodic minor, one octave each, naming the altered degrees as you reach them. All twelve roots, cycle order.
2. Spell them. Pick a minor key, write its key signature (the relative major's), spell natural minor, then raise the 7th for harmonic and the 6th for melodic. Check with the scale finder.
3. Two-octave fingering. The G melodic minor fingering above in all twelve keys by moving the root; then convert each to harmonic and natural minor by lowering the right notes.
4. Sing the difference. Play the root, sing the 6th and 7th of each scale in turn, then play them. The b6–7 gap in harmonic minor is the hardest; sing it slowly.
5. Ear. Ear trainer in scale mode with Aeolian, harmonic minor and melodic minor only.

Quiz