"There is nothing like "Vespers" in the literature of music," writes Robert Ashley in his liner notes; in Alvin Lucier's case the hype is justified, as showcased on the Vespers and Other Early Works compilation. In "Vespers," performers equipped with Sondols (sonar dolphin echolocation devices) move around the performing space, creating an image of it in the listener's perception. Though no stereo version can faithfully reproduce the music's spatial aspect, the version here is mesmerizingly beautiful. Lucier's pioneering work can be seen as the precursor of many developments in today's music. "Chambers" predates Toshiya Tsunoda's experiments recording with microphones inside closed spaces by 30 years; and the almost inaudible "Elegy for Albert Anastasia" (1963) is the forerunner of "lowercase" composers such as Francisco López, Bernhard Günter, and Steve Roden. Also included here is the long overdue reissue of 1967's "North American Time Capsule," where Lucier uses Sylvania vocoders to analyse and produce purely electronic versions of spoken and other sounds, as "a message to listeners who don't know about ...