SetClass

Explore the building blocks of modern harmony. This app lets you see, hear and manipulate pitch class sets, the foundation of post-tonal and atonal music theory.

EXPLORE
• Tap notes on the pitch wheel to build any chord or scale.
• See the Forte number, prime form, normal form and interval vector.
• Check transpositional and inversional symmetry.
• Open the K/Kh complex of any set to see which set classes include it or its complement.

FIND
• Tap notes on a keyboard, or type a Forte number (3-11, 6-Z44) or pitch-class numbers (0 4 7).
• Browse all 224 Forte set classes, with Z-relations, filtered by size.

TRANSFORM
• Transpose, invert and multiply (M5, M7) any set.
• Morph smoothly from one set to another.

CREATE
• Generate sets by cardinality, symmetry and density.
• Arrange sets into rhythmic sequences using P, T, I, R and RI operations, with every inversion level.
• Build a serial matrix from rows of 2 to 12 notes.
• See each set as geometry in tonal space, with symmetry axes.
• Export to MIDI and MusicXML.

LEARN
• A built-in theory guide.
• Analysis examples from Debussy, Schoenberg, Stravinsky, Berg, Messiaen and more, with links to scores.

Built for students, composers and theorists, from first-time learners to advanced analysis.