Speaking of Steve Reich, if you haven't yet listened to his glorious Music for 18 Musicians ensemble piece (duration: 55 minutes), do give it[1] a try.

An explanation of the composition and its structure:

http://www.18musicians.com/genreunique.html

http://www.boosey.com/pages/cr/catalogue/cat_detail?musicid=...

[1] https://m.youtube.com/watch?v=ZXJWO2FQ16c

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