SetClass

About this app

SetClass is an interactive tool for exploring Pitch Class Set Theory — the analytical framework behind atonal and post-tonal music, from Schoenberg and Webern to contemporary composers. BUILD & HEAR Tap notes on the chromatic wheel to construct any chord, scale, or pitch collection. Hear it instantly with a jazz piano soundfont or built-in synthesizer. EXPLORE THE THEORY • Normal form, prime form, and Forte number for every set • Interval vector analysis • Transpositional and inversional symmetry • Z-relation detection TRANSFORM Apply serial operations: transposition (T0–T11), inversion, retrograde, retrograde inversion, and multiplication (M5, M7, M11). Watch the geometry change in real time. COMPOSE & SEQUENCE • Sequencer: build rhythmic patterns with serial transformations, arpeggios, swing, gate, and glide • Melody Generator: create melodic lines with contour control (free, rising, falling, arch) • Morph: blend smoothly between two sets with optional portamento • Export to MIDI or MusicXML FIND & GENERATE • Set Finder: enter any melody or chord and identify the pitch class set inside • Generator: produce sets by cardinality, symmetry (mirror, symmetric), and density LEARN Built-in theory reference covering pitch classes, normal form, prime form, interval vectors, Forte numbers, transposition, inversion, retrograde, symmetry, Z-relation, set class, morphing, and serial technique — with musical examples from Debussy, Schoenberg, Bartók, Webern, Berg, Stravinsky, and Messiaen. Available in English, Spanish, French, Italian, German, and Chinese.

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1. First observed Aug 12, 2026 · 5:24 PM $4.99