S.E.M. Ensemble has been played on NTS in shows including Post-Geography, featured first on 4 December 2020. Songs played include Concert For Piano And Orchestra.

Founded in 1970 by Petr Kotik, S.E.M. Ensemble is dedicated to the performance and advancement of new music. Kotik established The Orchestra of the S.E.M. Ensemble in 1992, with its Carnegie Hall performance of “A Tribute to John Cage.” Since this concert, SEM Orchestra has toured Europe five times and, in 1997, performed at the Toru Takemitsu Memorial Concert in Tokyo. In New York, the orchestra has presented major concerts at Alice Tully Hall, Merkin Concert Hall, the Winter Garden of the World Financial Center, and Willow Place Auditorium in Brooklyn. SEM Orchestra has released recordings on Wergo, Asphodel, and Dog w/a Bone labels.

Since 1999 S.E.M. has been collaborating with the Janacek Philharmonic Orchestra, one of the 5 major orchestras of the Czech Republic. Together they have created a repertoire of works for 3 orchestras, which includes Gruppen by Karlheinz Stockhausen, Nest by Martin Smolka, Modules I,II,III by Earle Brown, and Diamonds by Alvin Lucier. These pieces were performed at the Prague Spring Festival, the Warsaw Autumn Festival and the Ostrava Days 2001 Festival, featuring the Orchestra of the S.E.M. Ensemble, the Janacek Philharmonic Orchestra, and conductors Petr Kotik, Christian Arming, and Zsolt Nagy.

Over the past ten years, the repertoire of SEM has included compositions by Brown, Wolff, Lucier, Cage, Feldman, Kotik, Phil Niblock, Somei Satoh, Roscoe Mitchell, Henry Threadgill, Muhal Richard Abrams, Leroy Jenkins, Robin Haller, and Sinan Savaskan. This repertoire, much of it written specifically for the orchestra, represents the core of SEM’s artistic and intellectual pursuits. S.E.M. Ensemble have produced the sound recording of the complete musical works of Marcel Duchamp, amongst other enterprises.