Harmony generation uses AI to create chord progressions and multi-voice arrangements — generating chords that support melodies, creating harmonic movement, tension, and resolution that gives music emotional depth and structural foundation.

What Is Harmony Generation?

• Definition: AI creation of chords and chord progressions.
• Output: Chord sequences, multi-voice MIDI, figured bass.
• Goal: Musically pleasing harmonic support for melodies.

Harmonic Elements

Chords: Multiple notes played together (triads, 7ths, extensions). Progressions: Sequence of chords (I-IV-V-I, ii-V-I). Voice Leading: Smooth movement between chord tones. Cadences: Harmonic endings (authentic, plagal, deceptive). Modulation: Key changes within piece.

Common Progressions: I-V-vi-IV (pop), ii-V-I (jazz), I-IV-I-V (blues), i-VI-III-VII (minor).

AI Approaches: Rule-based (music theory), probabilistic (Markov chains), neural networks (RNNs, transformers), constraint satisfaction.

Applications: Accompaniment generation, reharmonization, jazz comping, orchestration.

Tools: Hookpad, ChordAI, Chordbot, Band-in-a-Box, Magenta Coconet.