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Philip Glass (born January 31, 1937) is an American composer. He is widely regarded as one of the most influential musicians of the late 20th century. Glass's work has been described as minimal music, having similar qualities to other "minimalist" composers such as La Monte Young, Steve Reich, and Terry Riley. However, Glass has instead described himself as a composer of "music with repetitive structures", which he has helped evolve stylistically.

In the late 1990s and early 2000s, Glass's lyrical and romantic styles peaked with a variety of projects: operas, theatre and film scores (Martin Scorsese's Kundun, 1997, Godfrey Reggio's Naqoyqatsi, 2002, and Stephen Daldry's The Hours, 2002), a series of five concerts, and three symphonies centered on orchestra-singer and orchestra-chorus interplay. Two symphonies, Symphony No. 5 "Choral" (1999) and Symphony No. 7 "Toltec" (2004), and the song cycle Songs of Milarepa (1997) have a meditative theme. The operatic Symphony No. 6 Plutonian Ode (2002) for soprano and orchestra was commissioned by the Brucknerhaus, Linz, and Carnegie Hall in celebration of Glass's sixty-fifth birthday, and developed from Glass's collaboration with Allen Ginsberg (poet, piano - Ginsberg, Glass), based on his poem of the same name. Besides writing for the concert hall, Glass continued his ongoing operatic series with adaptions from literary texts: The Marriages of Zones 3, 4 and 5 ([1997] story-libretto by Doris Lessing), In the Penal Colony (2000, after the story by Franz Kafka), and the chamber opera The Sound of a Voice (2003, with David Henry Hwang), which features the Pipa, performed by Wu Man at its premiere. Glass also collaborated again with the co-author of Einstein on the Beach, Robert Wilson, on Monsters of Grace (1998), and created a biographic opera on the life of astronomer Galileo Galilei (2001). In the early 2000s, Glass started a series of five concerti with the Tirol Concerto for Piano and Orchestra (2000, premiered by Dennis Russell Davies as conductor and soloist), and the Concerto Fantasy for Two Timpanists and Orchestra (2000, for the timpanist Jonathan Haas). The Concerto for Cello and Orchestra (2001) had its premiere performance in Beijing, featuring cellist Julian Lloyd Webber; it was composed in celebration of his fiftieth birthday. These concertos were followed by the concise and rigorously neo-baroque Concerto for Harpsichord and Orchestra (2002), demonstrating in its transparent, chamber orchestral textures Glass's classical technique, evocative in the "improvisatory chords" of its beginning a toccata of Froberger or Frescobaldi, and 18th century music. Two years later, the concerti series continued with Piano Concerto No. 2: After Lewis and Clark (2004), composed for the pianist Paul Barnes. The concerto celebrates the pioneers' trek across North America, and the second movement features a duet for piano and Native American flute. With the chamber opera The Sound of a Voice, Glass's Piano Concerto No. 2 might be regarded as bridging his traditional compositions and his more popular excursions to World Music, also found in Orion (also composed in 2004).

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In the early 2000s, Glass started a series of five concerti with the Tirol Concerto for Piano and Orchestra