ABSTRACT
Set theory provides a way to uncover the organization of post-tonal music by identifying interrelated and recurring groups, or sets, of pitch classes. Set theory relies on the concepts of pitch class and pitch-class space. Integers represent pitch classes, and the pitch-class wheel is used to model and analyze relationships among pitch classes and sets of pitch classes. Alternative pitch collections and chord types give rise to new sound worlds, and pitch centers—when present—are established on a contextual basis. A pitch-class set (pc) may be transposed and inverted in pitch-class space. Applying either of the operations maps the original pitch classes of the set onto new pitch classes but preserves the interval-class content of the set. Transposition in pc space is equivalent to rotation on the pc wheel. A T-operation rotates every pitch class of a pc set by a certain number of pc semitones.
