PHILIP GLASS: "DANCEPIECES" ("IN THE UPPER ROOM"; "GLASSPIECES"). Philip Glass Ensemble conducted by Michael Riesman. CBS MK 39539 (compact disc). Music to unwind by. These two loosely structured cycles were put together for choreographers Jerome Robbins ("Glasspieces," 1983) and Twyla Tharp ("In the Upper Room," 1986). Glass's minimalism (endlessly broken arpeggios and intervals in slightly varied but highly repetitive patterns, with heavy amplification) bores after a certain point and neither of these works is really interesting enough to stand on its own without choreography. The most substantial offerings are "Glasspiece No. 2 (Facades)," a haunting, Bellinian aria for soprano sax with gently pulsating string accompaniment; and "Glasspiece No. 3," the music for the funeral procession from Glass's opera "Akhnaten," whose sexy, sinister drumming creates a hypnotically ceremonial atmosphere. The sound is silky smooth.