POLYPHONIC SPREE If you've got any real mileage on your odometer, it may seem weird to talk about this act as seminal because it doesn't seem that long ago that Dallas native Tim DeLaughter and his robed choir took SXSW and "the music industry" (look it up) by storm in 2000. But holy shit, a lot has gone on in that span. Back then, the idea of a mega-band built around orchestral and rock elements (flute, trumpet, trombone, violin, viola, cello, glockenspiels and the electric stuff) seemed kinda novel. You could argue that the Spree has since spawned the whole orchestral rock rebirth (Sufjan Stevens' winged string section angels, Arcade Fire's roaring choruses), but then their debt to the Beatles and The Soft Bulletin-era Flaming Lips is just as apparent. Still, there's just something about a roomful of people singing their hearts and lungs out. $19.50-$27.50. McGlohon Theater.