Class: Musa::Scales::MinorNaturalScaleKind

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

Overview

Natural minor scale kind (Aeolian mode).

MinorNaturalScaleKind defines the natural minor scale, parallel to the major scale but with a darker, melancholic character. It follows the pattern: W-H-W-W-H-W-W or intervals: M2-m2-M2-M2-m2-M2-M2 from the root.

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 (subtonic): Minor seventh (10 semitones, NOT leading tone)

Extended degrees: viii-xiii (compound intervals)

Differences from Major

Compared to major scale (same tonic):

  • iii: Flatted third (minor third instead of major)
  • vi: Flatted sixth (minor sixth instead of major)
  • vii: Flatted seventh (minor seventh instead of major)

Relative Major

The iii degree is the root of the relative major scale (shares same notes but different tonic). For example:

  • A minor (natural) relative major: C major
  • C major relative minor: A minor

Function Aliases

Similar to major but with lowercase Roman numerals:

  • Numeric: _1, _2, _3, _4, _5, _6, _7
  • Roman: i, ii, iii, iv, v, vi, vii
  • Function: tonic, supertonic, mediant, subdominant, dominant, submediant
  • Ordinal: first, second, third, fourth, fifth, sixth, seventh
  • Special: relative/relative_major for iii

Usage

a_minor = Scales[:et12][440.0][:minor][69]
a_minor.tonic        # A (69)
a_minor.dominant     # E (76)
a_minor.iii          # C (72) - relative major root
a_minor.relative_major.scale(:major)  # C major scale

See Also:

Constant Summary collapse

@@pitches = 
{ functions: %i[i _1 tonic first],
pitch: 0 },
             { functions: %i[ii _2 supertonic second],
pitch: 2 },
             { functions: %i[iii _3 mediant relative relative_major third],
pitch: 3 },
             { functions: %i[iv _4 subdominant fourth],
pitch: 5 },
             { functions: %i[v _5 dominant fifth],
pitch: 7 },
             { functions: %i[vi _6 submediant sixth],
pitch: 8 },
             { functions: %i[vii _7 seventh],
pitch: 10 },
             { functions: %i[viii _8 eighth],
pitch: 12 },
             { functions: %i[ix _9 ninth],
pitch: 12 + 2 },
             { functions: %i[x _10 tenth],
pitch: 12 + 3 },
             { functions: %i[xi _11 eleventh],
pitch: 12 + 5 },
             { functions: %i[xii _12 twelfth],
pitch: 12 + 7 },
             { functions: %i[xiii _13 thirteenth],
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



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# File 'lib/musa-dsl/music/equally-tempered-12-tone-scale-system.rb', line 396

def grades
  7
end

.id ⇒ Symbol

Scale kind identifier.

Returns:

  • (Symbol) —

    :minor



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# File 'lib/musa-dsl/music/equally-tempered-12-tone-scale-system.rb', line 402

def id
  :minor
end

.pitches ⇒ Array<Hash>

Pitch structure.

Returns:

  • (Array<Hash>) —

    pitch definitions with functions and offsets



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# File 'lib/musa-dsl/music/equally-tempered-12-tone-scale-system.rb', line 390

def pitches
  @@pitches
end