Steve Reich has always been one of my favorites among the modernists. His penchant for creating overlapping rhythms that sound like an artificial effect has always been a distinguishing factor in his music.
He is often described as a minimalist, in this case utilizing only eighteen musicians in this piece, foregoing the grandiose symphony orchestra to see what he can do with less. And, boy, does he get the most out of this small ensemble. The entire piece is a convergence of harmony and rhythm in a way that tricks your brain into hearing things that aren't there or that it thinks it hasn't heard before.