Steve Reich, “Music for Pieces of Wood,” 1973
"Pieces of Wood calls for five musicians, each playing a pair of claves — essentially, a short, tuned wooden rod struck against another. Modeled according to Reich’s much-favored phasing technique, a single rhythmic figure is offset and overlapped with itself in a constantly evolving composite texture.
The music begins simply enough: the first player lays down a featureless, metronomic beat that continues throughout the piece. The second player then joins in with a repeating twelve-note pattern. The other players join in one by one playing the same pattern as the second player, either in unison with him or offset by a few beats. When they enter, however, each does so note-by-note, so that several repetitions are necessary before they are playing the entire pattern. Because each clave is tuned to a specific pitch (the score includes detailed instructions regarding the sanding and boring required for proper tuning), an overall melodic and rhythmic texture slowly takes shape until a surprisingly complex web of composite sound emerges. This idea is then reversed as each of the players in turn begins to discreetly omit note after note from his pattern, until nothing but the original metronomic beat remains. This entire build-up/tear-down plan is repeated with shorter and shorter rhythmic patterns, until the process is completely exhausted.”