Class: Musa::Scales::MinorHarmonicScaleKind

Inherits:
ScaleKind show all
Defined in:
lib/musa-dsl/music/equally-tempered-12-tone-scale-system.rb

Overview

Harmonic minor scale kind.

MinorHarmonicScaleKind defines the harmonic minor scale, a variation of the natural minor with a raised seventh degree. This creates a leading tone (major seventh) that resolves strongly to the tonic, giving the scale a more directed, dramatic character.

Pitch Structure

7 diatonic degrees plus extended harmony (8th-13th):

Scale Degrees (Roman numerals, lowercase for minor):

  • i (tonic): Root (0 semitones)
  • ii (supertonic): Major second (2 semitones)
  • iii (mediant): Minor third (3 semitones, relative major)
  • iv (subdominant): Perfect fourth (5 semitones)
  • v (dominant): Perfect fifth (7 semitones)
  • vi (submediant): Minor sixth (8 semitones)
  • vii (leading): Major seventh (11 semitones) ← RAISED from natural minor

Extended degrees: viii-xiii (compound intervals)

Key Difference from Natural Minor

The vii degree is raised from 10 semitones (minor seventh) to 11 semitones (major seventh), creating:

  • A leading tone that resolves strongly upward to the tonic
  • An augmented second interval between vi and vii (3 semitones)
  • A dominant seventh chord (v7) with strong resolution to i

Musical Character

The harmonic minor scale:

  • Maintains minor quality (minor third)
  • Provides strong dominant-to-tonic resolution
  • Creates exotic sound due to augmented second (vi-vii)
  • Common in classical, jazz, and Middle Eastern music

Function Aliases

Same as natural minor:

  • Numeric: _1, _2, _3, _4, _5, _6, _7
  • Roman: i, ii, iii, iv, v, vi, vii
  • Function: tonic, supertonic, mediant, subdominant, dominant, submediant, leading
  • Special: relative/relative_major for iii

Usage

a_harmonic_minor = Scales[:et12][440.0][:minor_harmonic][69]
a_harmonic_minor.vii  # G# (80) - raised 7th, not G (79)
a_harmonic_minor.vi   # F (77)
# Augmented second: F to G# = 3 semitones

See Also:

Constant Summary collapse

@@pitches = 
{ functions: %i[i _1 tonic],
pitch: 0 },
             { functions: %i[ii _2 supertonic],
pitch: 2 },
             { functions: %i[iii _3 mediant relative relative_major],
pitch: 3 },
             { functions: %i[iv _4 subdominant],
pitch: 5 },
             { functions: %i[v _5 dominant],
pitch: 7 },
             { functions: %i[vi _6 submediant],
pitch: 8 },
             { functions: %i[vii _7 leading],
pitch: 11 },
             { functions: %i[viii _8],
pitch: 12 },
             { functions: %i[ix _9],
pitch: 12 + 2 },
             { functions: %i[x _10],
pitch: 12 + 3 },
             { functions: %i[xi _11],
pitch: 12 + 5 },
             { functions: %i[xii _12],
pitch: 12 + 7 },
             { functions: %i[xiii _13],
pitch: 12 + 8 }].freeze

Class Method Summary collapse

Constructor Details

This class inherits a constructor from Musa::Scales::ScaleKind

Class Method Details

.grades ⇒ Integer

Number of diatonic degrees.

Returns:

  • (Integer) —

    7



509
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# File 'lib/musa-dsl/music/equally-tempered-12-tone-scale-system.rb', line 509

def grades
  7
end

.id ⇒ Symbol

Scale kind identifier.

Returns:

  • (Symbol) —

    :minor_harmonic



515
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# File 'lib/musa-dsl/music/equally-tempered-12-tone-scale-system.rb', line 515

def id
  :minor_harmonic
end

.pitches ⇒ Array<Hash>

Pitch structure.

Returns:

  • (Array<Hash>) —

    pitch definitions with functions and offsets



503
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# File 'lib/musa-dsl/music/equally-tempered-12-tone-scale-system.rb', line 503

def pitches
  @@pitches
end