The Flow of (u) is a pieces for three soprano voices by Kenneth Gaburo written in 1974.
Warren Burt (2002), explains that the piece consists of "one note sung by three singers for twenty-three minutes" on u whose goal is "to sing in tune to such an extant that...this would consist of phase-coherent waves of sound." This, however, proves impossible, as singers must breathe, beating occurs between nearly in tune pitches, and the spectrum or harmonics: "Gently changing balances between the voices would result in very sublte glissandi of the harmonics of the spectrum being heard." The piece creates a, "(sonic) universe in this (linguistic) 'grain of sand.'"
He also contends that unlike other minimalist works, in which, compared to serial music, "a certain level of articulational subtelty is eschewed in favor of an overall psycho-acoustic effect," however, in Gaburo's piece, "the focus is even more intense, and the attention to dynamic shaping given to the lines...is here transferred to the micro-level."
