Harmonic Toolkit for Composers

Interactive tools for finding and hearing pitch material: traditional chords and keys, symmetric scales, spectral chords, modes of limited transposition, all-interval chords, and the ranges of the orchestra. Every tool shows its results on the 88 keys of the piano.

Scales, modes and chords

Traditional Chords

Traditional tonal chords (triads, sixths, sevenths and ninths) spelled correctly in every key, with inversions. Click a key on the circle of fifths to see the chords that belong to it.

Messiaen modes

The seven modes of limited transposition from Messiaen's Technique de mon langage musical (1944). Choose a mode and a transposition to see which pitches belong to it.

All-interval chords

Chords that contain every interval exactly once: the two all-interval tetrachords, chains built from them, twelve-note all-interval rows, and the microtonal systems where larger ones exist.

Spectral Analysis

Choose any combination of pitches. The tool merges their harmonic series into one master spectrum and searches for a single virtual fundamental that could explain the whole chord.

Lindberg scales

Pick an inversionally symmetric hexachord and a bass note. The tool builds Magnus Lindberg's 12-note chord (two complementary hexachords voiced across five octaves) and adds the partials of its virtual fundamental.

Orchestration

Instrument ranges

The practical range and register colours of each orchestral instrument, with transpositions and playing notes, so you can check where your chords will actually sit.