Remember, y'all, that pnoom started this thread with two names, Philip Glass and Karlheinz Stockhausen.
Our recommendations should really be more congruent (like those on Art Rock's list) with one or the other of those two composers (who are not noticably congruent with each other, really. How'd you run across Stockhausen, pnoom?).
Anyway, from early Glass, you might go to Andriessen or even early Reich. From later Glass, you might go to Adams or Kutavicius. (I hate saying those two in the same breath, as I detest Adams and adore Kutavicius, but this isn't about me!)
Of all the west coast minimalists, I like Chas Smith, who builds his own instruments, best, though Jim Fox and Rick Cox and the good Adams (John Luther) have all done great stuff.
Of the original minimalists, LaMonte Young and Tony Conrad are still the two biggies. Tony's stuff can be every bit as harsh as Stockhausen's, and even more relentless. The four CD set, Tony Conrad, Early Minimalism, Vol. 1, is to die for. (There is no Vol. 2, by the way.)
Once you're hooked by Stockhausen, you'll likely want other electroacoustic music. That's a huge area of music, largely unexplored by people who listen to the standard concert repertoire, but healthy and growing nonetheless!
Whenever you like, I'll give you a name or two from that world. Oh, it's fun!
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