Six Pianos

Six Pianos is a minimalist piece for six pianos by the American composer Steve Reich. It was completed in March 1973. He also composed a variation for six marimbas, called Six Marimbas, in 1986. The world première performance of Six Pianos was in May 1973 at the John Weber Gallery in New York City. The European première took place in January the next year in Stuttgart, Germany.

Reich's idea was originally for a piece titled "Piano Store" that could be played on all the pianos in a piano store. A friend in New York gave him and his fellow musicians access to the Baldwin Piano and Organ Company's premises during evenings, where they could try out ideas. Reich eventually settled on an ensemble of six upright pianos in close proximity, which would allow very precise timing without being masked by the resonance of grand pianos.

The piece begins with three pianists playing different notes to the same 8-beat rhythmic pattern. Then two more pianists begin to play the same pattern shifted two beats out of phase. (Phasing is a prominent technique in most of Steve Reich's work.) Different phase shifts of the same motifs fade in and out of the ever-changing musical texture for the duration of the piece. The piece also uses the additive technique of gradually building up parts by substituting notes for rests, and the opposite.Six Pianos is also notable by being one of Reich's only pieces in duple time.

Six Pianos has three sections, separated by relatively sudden changes of tonal center, though they all use the same seven pitch classes of the D major diatonic scale. The first section is in D major, with the tonality anchored in place by a persistent pattern of D and A in the bass. Then that pattern slowly fades out, leaving a B minor tonality which serves as a short transition to the second section in E Dorian. A sudden transition leads to the third section in B natural minor. Six Marimbas follows the same structure, but is transposed down by one semitone so that the piece opens in D flat major and concludes in B flat natural minor.

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