A Form Atom defined by self-contained constructional properties representing a historical corpus of music and contained within metadata of the Form Atom is disclosed. The Form Atom has a generative set of heuristics to support generation of a set of chords in a chord scheme or many different sets of chords. The generated chords are spaced out within a defined window of musical time by chord spacer heuristics. The Form Atom has a tag describing its compositional heuristics. A chord list of the Form Atom is provided in local tonic and defines branching structures that may be used for the generation of different chords from the local tonic. A progression descriptor is combined with a form function such that the Form Atom expresses musically a question, an answer and a statement. A meta-map of a chord scheme for a musical section is created from the metadata.

A method and system for analyzing patterns in the relationships of notes of an input piece of music. The method comprises generating a set of the most frequently occurring note pitches in ascending pitch order that matches an interval pattern, and detecting out-of-key pitches that lie outside of this interval pattern. One or more potential key sequence bifurcations are identified which represent a list of possible key sequences according to forwards and backwards analysis. By finding patterns of repetition in the chordal sequences that may be generated according to these key sequence bifurcations, a key sequence that allows the most frequently recurring chord sequences may be chosen. Chord sequences may be analyzed by using ghost chords, temporary harmonic structures that are created, updated and finalized over time according to a combination of essential and inessential note fragments. The method further comprises identifying non-harmony pitches according to the analyzed chord sequence.