The Velvet Underground, which was originally sponsored by Andy Warhol and showcased the songwriting of John Cale as well as Mr. Reed, wrought gradual but profound impact on the high-I.Q., low-virtuosity stratum of punk, alternative and underground rock around the world. Joy Division, Talking Heads, Patti Smith, R.E.M., the Strokes and numerous others were descendants. The composer Brian Eno, in an often-quoted interview from 1982, suggested that if the group’s first album, “The Velvet Underground & Nico,” sold only 30,000 copies during its first five years — a figure probably lower than the reality — “everyone who bought one of those 30,000 copies started a band.”

Many of the group’s themes — among them love, sexual deviance, alienation, addiction, joy and spiritual transfiguration — stayed in Mr. Reed’s work through his long run of solo recordings. Among the most noteworthy of those records were “Transformer” (1972), “Berlin” (1973) and “New York” (1989). The most notorious, without question, was “Metal Machine Music” (1975).

Beloved of Mr. Reed and not too many others, “Metal Machine Music” was four sides of electric-guitar feedback strobing between two amplifiers, with Mr. Reed altering the speed of the tape recorder; no singing, no drums, no stated key. At the time it was mostly understood, if at all, as a riddle about artistic intent. Was it his truest self? Was it a joke? Or was there no difference?

Mr. Reed wrote in the liner notes that “no one I know has listened to it all the way through, including myself,” but he also defended it as the next step after La Monte Young’s early minimalism. “There’s infinite ways of listening to it,” he told the critic Lester Bangs in 1976.

Not too long after his first recordings, made at 16 with a doo-wop band in Freeport, N.Y., Mr. Reed started singing outside of the song’s melody, as if he were giving a speech with a fluctuating drone in a New York accent. That sound, heard with the Velvet Underground on songs like “Heroin” and “Sweet Jane” and in his post-Velvet songs “Walk on the Wild Side,” “Street Hassle” and others, became one of the most familiar frequencies in rock. He played lead guitar the same way, straining against his limitations.