A founding member of The Velvet Underground, Welsh-born classically trained John Cale left the band in 1968 to pursue a solo career. Playing various keyboards, guitars, and other stringed instruments, his sound has varied widely including excursions into avant-garde, art rock, experimental rock, classical, drone music, and even proto-punk (as he produced The Stooges' first record). While his first several albums remain his most accessible, he later branched out into more challenging work, often confrontational and stark.