Micropolyphony
Micropolyphony is a kind of polyphonic musical texture developed by György Ligeti and then imitated by some other twentieth-century composers, which consists of many lines of dense canons moving at different tempos or rhythms, thus resulting in tone clusters vertically. According to David Cope, "micropolyphony resembles cluster chords, but differs in its use of moving rather than static lines"; it is "a simultaneity of different lines, rhythms, and timbres" (Cope 1997, 101).