Class: Musa::Scales::DiminishedHWScaleKind

Inherits:

ScaleKind

• Object
• ScaleKind
• Musa::Scales::DiminishedHWScaleKind

Defined in:

lib/musa-dsl/music/scale_kinds/symmetric/diminished_hw_scale_kind.rb

Overview

Diminished half-whole scale kind.

DiminishedHWScaleKind defines the half-whole diminished scale (also called octatonic scale), an eight-note symmetric scale alternating half steps and whole steps. It's commonly used over diminished 7th chords.

Pitch Structure

8 degrees plus extended:

Scale Degrees (pattern: H-W-H-W-H-W-H-W):

• i (_1): Root (0 semitones)
• ii (_2): Minor second (1 semitone)
• iii (_3): Minor third (3 semitones)
• iv (_4): Major third (4 semitones)
• v (_5): Diminished fifth (6 semitones)
• vi (_6): Perfect fifth (7 semitones)
• vii (_7): Major sixth (9 semitones)
• viii (_8): Minor seventh (10 semitones)

Symmetric Properties

• Only 3 distinct diminished scales exist
• Repeats every minor third (3 semitones)
• Contains 4 minor thirds, 4 major thirds, 2 tritones
• Every diminished 7th chord is contained within

Musical Character

The half-whole diminished scale:

• Tense, dark, unstable quality
• Used over diminished 7th chords
• Common in jazz, film scores, classical
• Creates strong chromatic tension

Usage

c_dim = Scales[:et12][440.0][:diminished_hw][60]
c_dim[0].pitch  # C (60)
c_dim[1].pitch  # Db (61)

See Also:

• Abstract base class
• Whole-half diminished (dominant diminished)
• Whole tone scale

Constant Summary

@@pitches =

[{ functions: i[i _1 tonic first],
pitch: 0 },
             { functions: i[ii _2 second],
pitch: 1 },
             { functions: i[iii _3 third],
pitch: 3 },
             { functions: i[iv _4 fourth],
pitch: 4 },
             { functions: i[v _5 fifth],
pitch: 6 },
             { functions: i[vi _6 sixth],
pitch: 7 },
             { functions: i[vii _7 seventh],
pitch: 9 },
             { functions: i[viii _8 eighth],
pitch: 10 },
             { functions: i[ix _9 ninth],
pitch: 12 },
             { functions: i[x _10 tenth],
pitch: 12 + 1 },
             { functions: i[xi _11 eleventh],
pitch: 12 + 3 },
             { functions: i[xii _12 twelfth],
pitch: 12 + 4 },
             { functions: i[xiii _13 thirteenth],
pitch: 12 + 6 },
             { functions: i[xiv _14 fourteenth],
pitch: 12 + 7 },
             { functions: i[xv _15 fifteenth],
pitch: 12 + 9 },
             { functions: i[xvi _16 sixteenth],
pitch: 12 + 10 }].freeze

Class Method Summary

• .grades ⇒ Object
• .id ⇒ Object
• .pitches ⇒ Object

Constructor Details

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

Class Method Details

.grades ⇒ Object

# File 'lib/musa-dsl/music/scale_kinds/symmetric/diminished_hw_scale_kind.rb', line 98

def grades
  8
end

.id ⇒ Object

# File 'lib/musa-dsl/music/scale_kinds/symmetric/diminished_hw_scale_kind.rb', line 102

def id
  :diminished_hw
end

.pitches ⇒ Object

# File 'lib/musa-dsl/music/scale_kinds/symmetric/diminished_hw_scale_kind.rb', line 94

def pitches
  @@pitches
end