jameswenzel / cable

A fretted instrument chord generator written in Python

Cable

A fretted instrument chord generator written in Python

Create a new instance of Cable, optionally specifying a tuning and maximum number of spanned frets. The defaults are shown here

from Cable import Cable, STANDARD, Note, Interval, Quality, Extension
cable = Cable(tuning=STANDARD, span=3)

Build chords by specifying the note and optionally added notes, bass, quality, and extension

# Bb major:
cable.generate(Note.Bb)

# Building chords:

# F# Power chord
cable.generate(Note.Fs, Interval.PERFECT_FIFTH, Interval.PERFECT_FOURTH)
# The above can also be written as:
cable.generate(Note.Fs, Interval.a4, Interval.a5)

# A#maj#11 chord
cable.generate(Note.As, # Sharp/flat notes are succeded by s or b
               Interval.M7,  # capital M for a major 2nd, 3rd, 6th, or 7th. Lowercase m for minor
               Interval.a9,  # Standard added intervals are preceded by the letter 'a'
               Interval.s11, # Sharp/flat intervals are preceded by s or b
               quality=Quality.MAJ)
# Can also be written as:
cable.generate(Note.As,
               quality=Quality.MAJ,
               extension=Extension.s11)  # Sharp/flat extensions are preceded by s/b

# Bb9/F# chord:
cable.generate(Note.Bb,
               bass=Note.Fs,
               extension=Extension.E9)  # Unmodified extensions are preceded by E

Create a new tuning of any length by creating a list of notes:

BASS_DROP_D = [Note.D, Note.A, Note.D, Note.G]
cable = Cable(tuning=BASS_DROP_D)
FIVE_STRING_BASS = [Note.B, Note.E, Note.A, Note.D, Note.G]

cable's Issues

Inversions

Add support for specific inversions. In practice this might look very similar to slash chords.

Slash chords

Add support for slash chords.

Difficulty heuristics

While some chords are technically possible, they are difficult to play. Come up with heuristics for scoring difficulty, and sort the results accordingly.