The Desert Music

The Desert Music is a work of music for voices and orchestra composed by the minimalist composer Steve Reich. It is based on texts by William Carlos Williams and takes its title from his poetry anthology The Desert Music and Other Poems. The composition consists of five movements, and in both its tempi and arrangement of thematic material, the piece is in a characteristic arch form (ABCBA). It was composed in 1983.

The piece is scored for a chorus of 27 voices: nine sopranos, and six each of altos, tenors and basses.

The orchestra calls for:

The tempi between two sections are related by a ratio of 3:2, introduced at the end of each section by either tuplet or dotted rhythms, respectively. So, I and V have 192 bpm; II, IIIB, and IV have 128 bpm; IIIA and C have 85 bpm.

Sections I and V have the same harmonic structure, sections II and IV have both the same harmonic structure and the same words. Sections IIIA and IIIC have the same words.

The piece opens similarly to many of Reich's other works: a piano or mallet instrument pulsing on the beat, with another piano or marimba soon fading in on the offbeats (Music for 18 Musicians, Sextet, Three Movements for Orchestra). Also characteristic of several of Reich's pieces, such as New York Counterpoint, Electric Counterpoint, Sextet, Music for 18 Musicians, Three Movements for Orchestra, the exposition of the pulse is followed by pulsed notes in the choir and orchestra fading in and out over the course of a chord progression. Also, the first movement prominently features a repeated rhythm found in several of the aforementioned works (In The Desert Music, however, the fourth and fifth note are tied together):

...
Wikipedia