Duration series

A duration row or duration series is an ordering of a set of durations, in analogy with the tone row or twelve-tone set.

Olivier Messiaen's "Mode de valeurs et d'intensités" is often cited as the first serial piece, but, as well as being predated by Babbitt, both lacks order and views each note as a unit, rather than composing each parameter separately. Messiaen had, however, previously used this chromatic duration series as an ordered set in the opening episode of "Turangalîla 2", a movement from the Turangalîla-Symphonie (1946–48).

In 1946 Milton Babbitt wrote "The Function of Set Structures in the Twelve-Tone System", outlining a theory of complete (total) serialism. Babbitt's Three Compositions for Piano (1947–48) uses the rhythmic set 5-1-4-2 (sum: 12), whose permutation and function varies with each piece. In the first piece this governs the number of attacks within phrases, in the second rhythms are generated as multiples of a unit. (for example: 5×, 1×, etc.)

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