Kronos.

Music  Commissions with the Kronos Quartet has reinvigorated Steve Reich's creativity reports the Winnipeg Free Press, thanks to their own record label Nonesuch. One of the latest collaborations is an elegy on 9/11, which drew on previous experience:

"Reich, the distinguished visiting composer at the Winnipeg Symphony Orchestra's New Music Festival next week, was four blocks away from the terrorist attack on the World Trade Center in 2001. A decade later, he completed WTC 9/11, a piece that incorporates recorded snippets of NORAD and New York City fire department transmissions on Sept. 11 as well as interviews with some of the composer's friends and neighbours in lower Manhattan.

"Reich took a similar approach toward the Holocaust in 1988's Different Trains, which also used recorded voices. As a Jewish child during the Second World War, Reich made cross-continental train trips in the U.S. as he shuttled between divorced parents in New York City and Los Angeles. As an adult, he confronted the idea that Jewish children in Europe would have taken a very different sort of train ride."

NPR have uploaded an entire concert featuring both pieces to YouTube.