Minor scales are essential in music theory, offering unique flavors to compositions. Natural, harmonic, and melodic minor scales each have distinct interval patterns, creating different moods and harmonic possibilities.

Understanding these scales helps musicians navigate key signatures and compose in minor keys. The raised scale degrees in harmonic and melodic minor scales add tension and resolution, enriching the musical palette for composers and performers alike.

Minor Scales

Constructing Minor Scales

• Construct natural, harmonic, and melodic minor scales from any given tonic note
• To construct a minor scale, start on the tonic note and follow the interval pattern specific to the type of minor scale (natural, harmonic, or melodic)
• The key signature of a minor key is determined by the accidentals needed to construct the harmonic minor scale
• Examples of tonic notes include C, D, E, F, G, A, and B

Interval Patterns in Minor Scales

• Natural minor scales are constructed using the interval pattern: whole step, half step, whole step, whole step, half step, whole step, whole step (W-H-W-W-H-W-W)
• Harmonic minor scales are constructed by raising the 7th scale degree of the natural minor scale by a half step
• Melodic minor scales have two forms: ascending and descending
  • The ascending form is constructed by raising the 6th and 7th scale degrees of the natural minor scale by a half step each
  • The descending form is identical to the natural minor scale

Minor Scale Types

Natural Minor Scale

• Natural minor scales have the interval pattern: whole step, half step, whole step, whole step, half step, whole step, whole step (W-H-W-W-H-W-W)
• Example: A natural minor scale - A B C D E F G A
• The natural minor scale is the foundation for the other minor scale types
• It maintains the minor 6th and minor 7th intervals from the tonic

Harmonic Minor Scale

• Harmonic minor scales have the interval pattern: whole step, half step, whole step, whole step, half step, whole step + half step, half step (W-H-W-W-H-W+H-H)
• The raised 7th scale degree in the harmonic minor scale creates an augmented 2nd interval between the 6th and 7th scale degrees
• Example: A harmonic minor scale - A B C D E F G# A
• The raised 7th scale degree creates a leading tone, which is a half step below the tonic and provides a strong sense of resolution

Melodic Minor Scale

• Melodic minor scales have two different interval patterns for their ascending and descending forms
  • Ascending form: whole step, half step, whole step, whole step, whole step, whole step, half step (W-H-W-W-W-W-H)
  • Descending form: same as the natural minor scale (W-H-W-W-H-W-W)
• Example: A melodic minor scale (ascending) - A B C D E F# G# A
• Example: A melodic minor scale (descending) - A G F E D C B A
• The different ascending and descending forms create a sense of resolution when descending back to the tonic

Melodic Minor Scale Forms

Ascending Form

• The ascending form of the melodic minor scale raises the 6th and 7th scale degrees by a half step each compared to the natural minor scale
• The raised 6th and 7th scale degrees create a major 6th and major 7th interval from the tonic, respectively
• Example: E melodic minor scale (ascending) - E F# G A B C# D# E
• The raised 6th scale degree is a half step below the raised 7th scale degree

Descending Form

• The descending form of the melodic minor scale is identical to the natural minor scale
• It does not have any raised scale degrees, maintaining the minor 6th and minor 7th intervals from the tonic
• Example: E melodic minor scale (descending) - E D C B A G F# E
• The descending form provides a smooth transition back to the tonic without the raised scale degrees

Harmonic vs Natural Minor Scales

Raised 7th Scale Degree in Harmonic Minor

• In the harmonic minor scale, the 7th scale degree is raised by a half step compared to the natural minor scale
• The raised 7th scale degree creates a leading tone, which is a half step below the tonic
• Example: D harmonic minor scale - D E F G A Bb C# D
• The raised 7th scale degree (C# in this example) provides a strong pull towards the tonic

Interval Differences

• The harmonic minor scale has an augmented 2nd interval between the 6th and 7th scale degrees due to the raised 7th scale degree
• The natural minor scale maintains the minor 6th and minor 7th intervals from the tonic
• Example: Compare D natural minor (D E F G A Bb C D) and D harmonic minor (D E F G A Bb C# D)
• The raised 7th scale degree in the harmonic minor scale creates a unique interval pattern and a distinct sound compared to the natural minor scale