NAME
Music::Cadence - Generate musical cadence chords
VERSION
version 0.1104
SYNOPSIS
use Music::Cadence;
my $mc = Music::Cadence->new;
my $chords = $mc->cadence;
# [['G','B','D'], ['C','E','G','C']]
$mc = Music::Cadence->new( octave => 4 );
$chords = $mc->cadence;
# [['G4','B4','D4'], ['C4','E4','G4','C5']]
$chords = $mc->cadence(
type => 'half',
leading => 2,
octave => 0,
);
# [['D','F','A'], ['G','B','D']]
$mc = Music::Cadence->new(
key => 'C#',
octave => 5,
);
$chords = $mc->cadence;
# [['G#5','C5','D#5'], ['C#5','F5','G#5','C#6']]
$mc = Music::Cadence->new(
key => 'C#',
octave => 5,
format => 'midi',
);
$chords = $mc->cadence;
# [['Gs5','C5','Ds5'], ['Cs5','F5','Gs5','Cs6']]
$mc = Music::Cadence->new(
key => 'C',
octave => 4,
format => 'midinum',
);
$chords = $mc->cadence;
# [[67,71,62], [60,64,67,72]]
$mc = Music::Cadence->new;
$chords = $mc->cadence(
octave => 4,
type => 'imperfect',
inversion => { 1 => 1, 2 => 1 },
);
# [['B4','D4','G4'], ['E4','G4','C4']]
$mc = Music::Cadence->new( seven => 1 );
$chords = $mc->cadence;
# [['G','B','D','F'], ['C','E','G','A#','C']]
DESCRIPTION
Music::Cadence
generates a pair of musical cadence chords.
These chords are usually added to the end of a musical phrase, and are used to suggest a sense of anticipation, pause, finality, etc.
ATTRIBUTES
key
The key or tonal center to use. Default: C
Examples: G#
, Eb
scale
The scale to use. Default: major
Supported scales are:
ionian / major
dorian
phrygian
lydian
mixolydian
aeolian / minor
locrian
octave
The octave to either append to named chord notes (for midi
or isobase
format) or to determine the correct midinum
note number.
Default: 0
If the format is midi
or isobase
, setting this to 0
means "do not append."
The midinum
range for this attribute is from -1
to 10
.
format
The output format to use. Default: isobase
(i.e. "bare note names")
If midi
, convert sharp #
to s
and flat b
to f
after chord generation.
If midinum
, convert notes to their numerical MIDI equivalents.
seven
Use seventh chords (of 4 notes). Default: 0
METHODS
new
$mc = Music::Cadence->new; # Use defaults
$mc = Music::Cadence->new( # Override defaults
key => $key,
scale => $scale,
octave => $octave,
format => $format,
seven => $seven,
);
Create a new Music::Cadence
object.
cadence
$chords = $mc->cadence; # Use defaults
$chords = $mc->cadence( # Override defaults
key => $key, # Default: C
scale => $scale, # Default: major
octave => $octave, # Default: 0
type => $type, # Default: perfect
leading => $leading, # Default: 1
variation => $variation, # Default: 1
inversion => $inversion, # Default: 0
);
Return an array reference of the chords of the cadence type based on the given key and scale name.
Supported cadences are:
deceptive
half
imperfect
perfect
plagal
The variation applies to the deceptive
and imperfect
cadences.
If the type is deceptive
, the variation determines the final chord. If it is set to 1
, the vi
chord is used. For 2
, the IV
chord is used.
If the type is imperfect
and there is no inversion, the variation determines the kind of perfect
cadence generated. For 1
, the highest voice is not the tonic. For 2
, the fifth chord is replaced with the seventh. So in a major key, the V
chord would be replaced with the vii diminished
chord.
For an imperfect
cadence, if the inversion is set to a hash reference of numbered keys, the values are the types of inversions to apply to the chords of the cadence. For example:
inversion => { 1 => 2, 2 => 1 },
Says, "Apply the second inversion to the first chord of the cadence, and apply the first inversion to the second chord."
To not apply an inversion to an inverted imperfect cadence chord, either do not include the numbered chord in the hash reference, or set its value to 0
zero.
The leading chord is a number (1-7) for each diatonic scale chord to use for the first half
cadence chord. For the key of C major
this is:
CM: 1
Dm: 2
Em: 3
FM: 4
GM: 5
Am: 6
Bo: 7
If an inversion is defined for the half
cadence, the chords are inverted as described above for the imperfect
cadence.
TO DO
Evaded cadence
SEE ALSO
The eg/cadence, t/01-methods.t and t/02-methods.t files in this distribution.
https://en.wikipedia.org/wiki/Cadence
https://www.musictheoryacademy.com/how-to-read-sheet-music/cadences/
AUTHOR
Gene Boggs <gene@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2019 by Gene Boggs.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.