Class: Musa::Scales::BebopDominantScaleKind Private

Inherits:
ScaleKind show all
Defined in:
lib/musa-dsl/music/scale_kinds/bebop/bebop_dominant_scale_kind.rb

Overview

This class is part of a private API. You should avoid using this class if possible, as it may be removed or be changed in the future.

Bebop dominant scale kind.

BebopDominantScaleKind defines the bebop dominant scale, an eight-note scale that adds a chromatic passing tone (major 7th) to the Mixolydian mode. This allows chord tones to fall on downbeats during eighth-note runs.

Pitch Structure

8 degrees plus extended:

Scale Degrees (uppercase for major quality):

  • I (tonic): Root (0 semitones)
  • II (supertonic): Major second (2 semitones)
  • III (mediant): Major third (4 semitones)
  • IV (subdominant): Perfect fourth (5 semitones)
  • V (dominant): Perfect fifth (7 semitones)
  • VI (submediant): Major sixth (9 semitones)
  • VII (subtonic): Minor seventh (10 semitones)
  • VII# (leading): Major seventh (11 semitones) ← PASSING TONE

Bebop Principle

The added chromatic note ensures that:

  • Chord tones (1, 3, 5, b7) fall on strong beats
  • Non-chord tones fall on weak beats
  • Creates smooth voice leading at tempo

Musical Character

The bebop dominant scale:

  • Essential for jazz improvisation over dominant 7th chords
  • Creates characteristic bebop sound at fast tempos
  • Used by Charlie Parker, Dizzy Gillespie, and bebop masters

Usage

g_bebop = Scales[:et12][440.0][:bebop_dominant][67]
g_bebop[0].pitch  # G (67) - root
g_bebop[6].pitch  # F (77) - minor 7th
g_bebop[7].pitch  # F# (78) - major 7th (chromatic passing)

See Also:

Constant Summary collapse

@@pitches =

This classvariable is part of a private API. You should avoid using this classvariable if possible, as it may be removed or be changed in the future. 

[{ functions: %i[I _1 tonic first],
pitch: 0 },
             { functions: %i[II _2 supertonic second],
pitch: 2 },
             { functions: %i[III _3 mediant third],
pitch: 4 },
             { functions: %i[IV _4 subdominant fourth],
pitch: 5 },
             { functions: %i[V _5 dominant fifth],
pitch: 7 },
             { functions: %i[VI _6 submediant sixth],
pitch: 9 },
             { functions: %i[VII _7 subtonic seventh],
pitch: 10 },
             { functions: %i[VII# _8 leading eighth],
pitch: 11 },
             { functions: %i[VIII _9 ninth],
pitch: 12 },
             { functions: %i[IX _10 tenth],
pitch: 12 + 2 },
             { functions: %i[X _11 eleventh],
pitch: 12 + 4 },
             { functions: %i[XI _12 twelfth],
pitch: 12 + 5 },
             { functions: %i[XII _13 thirteenth],
pitch: 12 + 7 },
             { functions: %i[XIII _14 fourteenth],
pitch: 12 + 9 },
             { functions: %i[XIV _15 fifteenth],
pitch: 12 + 10 },
             { functions: %i[XV _16 sixteenth],
pitch: 12 + 11 }].freeze

Class Method Summary collapse

Constructor Details

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

Class Method Details

.grades ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/musa-dsl/music/scale_kinds/bebop/bebop_dominant_scale_kind.rb', line 98

def grades
  8
end

.id ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/musa-dsl/music/scale_kinds/bebop/bebop_dominant_scale_kind.rb', line 102

def id
  :bebop_dominant
end

.pitches ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/musa-dsl/music/scale_kinds/bebop/bebop_dominant_scale_kind.rb', line 94

def pitches
  @@pitches
end