the opera world) Anna-Maria Martinez, soprano (still active in the opera world) Former members Stephen Erb, audio engineer Martin Goldray, keyboards Bob Telson, keyboards Steve Reich, keyboards Art Murphy, keyboards Steve Chambers, keyboards James Tenney, keyboards Robert Prado, trumpet, flute, and keyboards Richard Peck, woodwinds Jack Kripl, woodwinds Richard Landry, woodwinds David Crowell, woodwinds Joan La Barbara, voice and keyboards Iris Hiskey, voice and keyboards Dora Ohrenstein, voice and keyboards Barbara Benary, violin and voice David Behrman, viola Beverly Lauridsen, cello Seymour Barab, cello Kurt Munkacsi, audio engineer (now a studio producer) Films 1982 – Koyaanisqatsi. Directed by Godfrey Reggio. 1983 – Philip Glass. From Four American Composers. Directed by Peter Greenaway. 1988 – Powaqqatsi. Directed by Godfrey Reggio. 2002 – Naqoyqatsi. Directed by Godfrey Reggio. 2008 – Glass: A Portrait of Philip in Twelve Parts. Directed by Scott Hicks. References External links Ensemble American experimental musical groups American classical music groups Contemporary classical music ensembles Musical groups established in 1968