Nonesuch releases Pulitzer Prize–winning composer Steve Reich’s album WTC 9/11 on September 20, 2011. Commissioned for and recorded by Kronos Quartet, the title piece is scored for three string quartets and pre-recorded voices; it will be available for digital purchase at digital-music stores, including iTunes, Amazon, and the Nonesuch Store, next Tuesday, September 6. The album also includes Reich’s Mallet Quartet, performed by Sō Percussion, and Dance Patterns, featuring members of Steve Reich and Musicians, as well as a DVD with a live performance of Mallet Quartet by Sō Percussion. The full album may be pre-ordered now in the Nonesuch Store, where CD orders include a free download of the title piece starting September 6 and the complete album starting September 20.

WTC 9/11 (2010) reflects on the World Trade Center attacks of September 11, 2001, when Reich and his family lived only four blocks away from the site of the tragedy. “On 9/11 we were in Vermont, but our son, granddaughter, and daughter-in-law were all in our apartment. Our phone connection stayed open for six hours and our next-door neighbors were finally able to drive north out of the city with their family and ours. For us, 9/11 was not a media event,” the composer says.

The piece is scored for three string quartets; Kronos recorded all three parts for the album. WTC 9/11 also uses pre-recorded voices, the speakers’ final vowels and consonants elongated in a stop-motion sound technique that Reich says is the “means of connecting one person to another—harmonically.” Those voices and their texts belong to NORAD air traffic controllers, as they raised the alert that the airplanes were off course; FDNY workers on the scene; friends and former neighbors of the Reichs, recalling that day; and women who kept vigil, or Shmira, over the dead in a tent outside the Medical Examiner’s office, reading Psalms or Biblical passages. The relationship between Steve Reich and Kronos Quartet spans more than 20 years. This is the third quartet the composer has written for Kronos; all three have been recorded by Nonesuch. Kronos receives the Polar Music Prize in a ceremony at the Stockholm Concert Hall tonight.

Mallet Quartet (2009), co-commissioned and performed by Sō Percussion, is scored for two vibraphones and two five-octave marimbas. The New York Times said of a recent Carnegie Hall performance: “Sō Percussion’s energetic account … pointed up one of Mr. Reich’s current modes of propulsion: a two-tiered approach in which the rhythmically repetitive backdrop that listeners hear as Minimalist (and as the music’s distinctively Reichian signature) is offset by restless, melodically adventurous top lines. There were other contrasts here: the repeating figures, for marimbas, were dark and subdued, with a warm, wooden tone; the themes, played on vibraphones, were cool, bright and lively.”

Dance Patterns (2002) is Reich’s contribution to Thierry de Mey’s film Counterphrases of Anne Terese de Keersmaeker’s Choreography, for which several composers wrote short pieces. While the film was shown, the music was performed live by the Ictus Ensemble, which commissioned all the music. Scored for vibraphones, xylophones, and pianos, Dance Patterns features members of Steve Reich and Musicians on the Nonesuch recording.

To pre-order the complete album and receive a free download of the title piece starting September 6 and the complete album starting September 20, head to the Nonesuch Store now.