Minor Scales

There are three forms of the minor scale: natural minor (Aeolian), harmonic minor (raised 7th), and melodic minor (raised 6th and 7th ascending). Each serves a different harmonic purpose and sounds different. Most minor key music uses all three in combination, and understanding which form fits which context is the core of minor key harmony.

Natural Minor (Aeolian)

A natural minor: A B C D E F G A
Formula: W - H - W - W - H - W - W
Degrees: 1  2  ♭3  4  5  ♭6  ♭7

The default minor sound. Same notes as the relative major scale. The V chord in natural minor is a minor chord (Em7 in A minor), which has less pull toward the tonic than a dominant seventh. Used for most minor key melodies and harmonic progressions where a natural, unforced minor quality is desired.

Diatonic chords in A natural minor:
i    Am7     — tonic
ii°  Bm7♭5  — half-diminished
♭III Cmaj7   — relative major's tonic
iv   Dm7    — minor subdominant
v    Em7    — minor dominant (weaker pull)
♭VI  Fmaj7  — subtonic major
♭VII G7     — subtonic dominant (strong in rock, not classical)

Harmonic Minor

A harmonic minor: A B C D E F G# A
Formula: W - H - W - W - H - A2 - H
Degrees: 1  2  ♭3  4  5  ♭6   7

Raises the 7th to create a strong leading tone and a major V chord. The augmented second (m6 to maj7, here F to G#) is the distinctive sound — it gives harmonic minor its slightly exotic, dramatic quality. Used in classical music for cadences, in gypsy/flamenco styles, and in metal for fast scalar runs.

Key change from natural minor:
V chord: Em7 → E7   (minor dominant → dominant 7th, stronger resolution)
Leading tone: G → G# (half step below tonic → strong pull to A)

Melodic Minor

A melodic minor (jazz form): A B C D E F# G# A
Formula: W - H - W - W - W - W - H
Degrees: 1  2  ♭3  4  5   6   7

Classical form descends as natural minor.
Jazz form: same notes in both directions.

Raises both the 6th and 7th to smooth out the augmented second of harmonic minor while retaining the leading tone. The jazz version (ascending form used both ways) is treated as its own independent scale with rich modal possibilities.

Choosing Which Minor Scale

Over Im chord in jazz:     Dorian (natural minor with raised 6) often best
                           Natural minor for darker sound
                           Melodic minor for exotic major-minor ambiguity

Over V7 chord in minor key: Harmonic minor or Phrygian Dominant
                             (both contain the raised 7th / leading tone)
                             Altered scale for maximum jazz tension

For melodies in minor key:  Classical tradition uses melodic minor ascending
                             Natural minor descending
                             Jazz ignores this rule

The Minor Pentatonic

A simpler starting point than any of the three full minor scales: just take the natural minor scale and remove the 2nd and 6th degrees. What's left (A C D E G in A minor) works over both minor and dominant chords and avoids the tension notes that require careful handling in the full scales.