Music Theory Module¶

The opendaw_mcp.music_theory module provides shared music theory constants and helper functions that power the orchestration tools (create_genre_track, create_chord_progression, etc.). You can import and use these directly in your Python code.

Import¶

from opendaw_mcp.music_theory import (
    NOTE_TO_PITCH,
    CHORD_INTERVALS,
    SCALE_INTERVALS,
    GENRE_PRESETS,
    VALID_GENRES,
    VALID_CHORD_TYPES,
    VALID_SCALE_TYPES,
    chord_to_pitches,
    scale_to_pitches,
)

Note → Pitch¶

NOTE_TO_PITCH maps note names to semitone offsets from C:

NOTE_TO_PITCH["C"]   # 0
NOTE_TO_PITCH["F#"]  # 6
NOTE_TO_PITCH["Bb"]  # 10
NOTE_TO_PITCH["Db"]  # 1  (enharmonic to C#)

Supports both sharps (C#, D#, F#, G#, A#) and flats (Db, Eb, Gb, Ab, Bb).

Chord Intervals¶

CHORD_INTERVALS maps chord type names to interval offset arrays:

Type	Intervals	Example
`maj`	[0, 4, 7]	C major: C-E-G
`min`	[0, 3, 7]	C minor: C-Eb-G
`dom7`	[0, 4, 7, 10]	C7: C-E-G-Bb
`maj7`	[0, 4, 7, 11]	Cmaj7: C-E-G-B
`min7`	[0, 3, 7, 10]	Cm7: C-Eb-G-Bb
`sus2`	[0, 2, 7]	Csus2: C-D-G
`sus4`	[0, 5, 7]	Csus4: C-F-G
`add9`	[0, 4, 7, 14]	Cadd9: C-E-G-D
`dim`	[0, 3, 6]	Cdim: C-Eb-Gb
`aug`	[0, 4, 8]	Caug: C-E-G#

Scale Intervals¶

SCALE_INTERVALS maps scale names to interval arrays:

Scale	Intervals
`major`	[0, 2, 4, 5, 7, 9, 11]
`minor` / `natural_minor`	[0, 2, 3, 5, 7, 8, 10]
`harmonic_minor`	[0, 2, 3, 5, 7, 8, 11]
`melodic_minor`	[0, 2, 3, 5, 7, 9, 11]
`dorian`	[0, 2, 3, 5, 7, 9, 10]
`phrygian`	[0, 1, 3, 5, 7, 8, 10]
`lydian`	[0, 2, 4, 6, 7, 9, 11]
`mixolydian`	[0, 2, 4, 5, 7, 9, 10]
`locrian`	[0, 1, 3, 5, 6, 8, 10]
`pentatonic_major`	[0, 2, 4, 7, 9]
`pentatonic_minor`	[0, 3, 5, 7, 10]
`blues`	[0, 3, 5, 6, 7, 10]
`chromatic`	[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]

Genre Presets¶

GENRE_PRESETS contains full genre templates used by create_genre_track:

GENRE_PRESETS["house"]
# {
#   "bpm": 128,
#   "drums": {"kick": "x...x...x...x...", "hihat": "....o...o...o..."},
#   "bass": [{"pitch": 36, "start": 0, "duration": 0.5}, ...],
#   "chords": [["F", "min7"], ["Ab", "maj7"], ["Db", "maj7"], ["Eb", "min7"]]
# }

Available genres: house, techno, lofi, dnb, trap, ambient, coldwave, hiphop

Each preset contains: - bpm — default tempo - drums — step-sequencer patterns (x = hit, o = soft, . = rest) - bass — list of {pitch, start, duration} notes - chords — list of [root, type] chord specs

Helper Functions¶

`chord_to_pitches(root, chord_type, octave=4)`¶

Convert a chord name to MIDI pitch numbers:

chord_to_pitches("C", "maj")       # [60, 64, 67]  — C4 major
chord_to_pitches("A", "min7")      # [69, 72, 76, 79]  — A4 minor 7
chord_to_pitches("F#", "min7", octave=3)  # [54, 57, 61, 64]  — F#3 minor 7

Octave 4 = MIDI 60 (middle C). Octave 3 = MIDI 48.

`scale_to_pitches(root, scale_type, octave=4, length=7)`¶

Generate MIDI pitches for a scale:

scale_to_pitches("C", "major")           # [60, 62, 64, 65, 67, 69, 71]
scale_to_pitches("A", "minor")           # [69, 71, 72, 74, 76, 77, 79]
scale_to_pitches("C", "blues", length=6) # [60, 63, 65, 66, 67, 70]
scale_to_pitches("A", "pentatonic_minor", length=5)  # [69, 72, 74, 76, 79]

When length exceeds the scale's interval count, the function wraps to the next octave.