Tone Clock · Subset Explorer

Forte identification, tessellation (T / TI), hour subsets, steerings, and repeated groups

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Identify a collection, list its intervals and hour triads, show how those instances are steered, and note repeated groups and mode membership.

Selection — keyboard or Forte class. Green keys are in the collection.
Identification — Forte name, prime form, interval pattern, complement.
Steerings — starting pitches of each interval type and each hour triad (the group those instances lie on).
Hour triads — every triad of hours I–XII in the collection, with form and path note.
Intervals — interval-class counts and instances.
Messiaen modes — whether the set is a subset of any transposition of Modes 1–7.
Tessellation — whether this collection can tile the aggregate by transposition only (T) or needs inversion (TI). T has a full reverse steering; TI reverse leaves an anchor remainder. Named cluster-scale T-fields: V⁴ / Cell Z, hexatonic III⁶, Mode 5 / IV-gemini.
Repeated subsets — subsets of cardinality 3 and above that occur more than once by transposition. In McLeod this is how a reverse steering is read from the Array Steerings: if interval (or group) x is steered by group y, the reverse is y steered by x.