Class: Musa::Scales::DiminishedWHScaleKind

Inherits:

ScaleKind

• Object
• ScaleKind
• Musa::Scales::DiminishedWHScaleKind

Defined in:

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

Overview

Diminished whole-half scale kind.

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

Pitch Structure

8 degrees plus extended:

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

• I (_1): Root (0 semitones)
• II (_2): Major second (2 semitones)
• III (_3): Minor third (3 semitones)
• IV (_4): Perfect fourth (5 semitones)
• V (_5): Diminished fifth (6 semitones)
• VI (_6): Augmented fifth (8 semitones)
• VII (_7): Major sixth (9 semitones)
• VIII (_8): Major seventh (11 semitones)

Symmetric Properties

• Only 3 distinct diminished scales exist
• Repeats every minor third (3 semitones)
• Same notes as half-whole, but different starting point
• Contains natural 9, #9, #11, 13 over dominant chord

Musical Character

The whole-half diminished scale:

• Used over dominant 7th chords (hence "dominant diminished")
• Provides b9, #9, #11, and natural 13 tensions
• Common in bebop and modern jazz
• Creates sophisticated altered dominant sound

Usage

g_dom_dim = Scales[:et12][440.0][:diminished_wh][67]
g_dom_dim[0].pitch  # G (67)
g_dom_dim[1].pitch  # A (69)

See Also:

• Abstract base class
• Half-whole diminished
• Altered scale (another dominant scale)

Constant Summary

@@pitches =

[{ functions: %i[I _1 tonic first],
pitch: 0 },
             { functions: %i[II _2 second],
pitch: 2 },
             { functions: %i[III _3 third],
pitch: 3 },
             { functions: %i[IV _4 fourth],
pitch: 5 },
             { functions: %i[V _5 fifth],
pitch: 6 },
             { functions: %i[VI _6 sixth],
pitch: 8 },
             { functions: %i[VII _7 seventh],
pitch: 9 },
             { functions: %i[VIII _8 eighth],
pitch: 11 },
             { functions: %i[IX _9 ninth],
pitch: 12 },
             { functions: %i[X _10 tenth],
pitch: 12 + 2 },
             { functions: %i[XI _11 eleventh],
pitch: 12 + 3 },
             { functions: %i[XII _12 twelfth],
pitch: 12 + 5 },
             { functions: %i[XIII _13 thirteenth],
pitch: 12 + 6 },
             { functions: %i[XIV _14 fourteenth],
pitch: 12 + 8 },
             { functions: %i[XV _15 fifteenth],
pitch: 12 + 9 },
             { functions: %i[XVI _16 sixteenth],
pitch: 12 + 11 }].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_wh_scale_kind.rb', line 98

def grades
  8
end

.id ⇒ Object

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

def id
  :diminished_wh
end

.pitches ⇒ Object

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

def pitches
  @@pitches
end