Chord Support

You can create chords with Octavian. Check out the release on npm.

const cMajorChord = new Octavian.Chord('C4', 'major');

cMajorChord.notes; // returns [ { letter: 'C', modifier: null, octave: 4 },
                   //           { letter: 'E', modifier: null, octave: 4 },
                   //           { letter: 'G', modifier: null, octave: 4 } ]

cMajorChord.signatures;  // returns [ 'C4', 'E4', 'G4' ]
cMajorChord.frequencies; // returns [ 261.626, 329.628, 391.995 ]
cMajorChord.pianoKeys;   // returns [ 40, 44, 47 ]

You can create the following chords:

• major
• majorSixth
• majorSeventh
• majorSeventhFlatFive
• majorSeventhSharpFive
• minor
• minorSixth
• minorSeventh
• minorMajor
• dominantSeventh
• diminished
• diminishedSeventh
• halfDimished

You're also more than welcome to use the following aliases for any of the above:

• maj is an alias for major
• 6 is an alias for majorSixth
• maj6 is an alias for majorSixth
• 7 is an alias for majorSeventh
• maj7 is an alias for majorSeventh
• maj7b5 is an alias for majorSeventhFlatFive
• maj7#5 is an alias for majorSeventhSharpFive
• min is an alias for minor
• m is an alias for minor
• min6 is an alias for minorSixth
• m6 is an alias for minorSixth
• min7 is an alias for minorSeventh
• m7 is an alias for minorSeventh
• m#7 is an alias for minorMajor
• min#7 is an alias for minorMajor
• m(maj7) is an alias for minorMajor
• dom7 is an alias for dominantSeventh
• dim is an alias for diminished
• dim7 is an alias for diminishedSeventh
• m7b5 is an alias for halfDiminshed

Adding Notes to a Chord

You can add notes to a chord manually, if that suits you:

const chord = new Octavian.Chord('C4');

chord.signatures; // returns ['C4']

chord.addInterval('majorThird');
chord.signatures; // returns ['C4', 'E4']

chord.addInterval(7);
chord.signatures; // returns ['C4', 'E4', 'G4']

Turning a Note into a Chord

You can turn any note into the basis for a chord:

const note = new Octavian.Note('C4');
note.toChord(); // returns a new chord with only C4 in it.
note.toChord('major'); // returns a new chord with C4, E4, and G4 in it