The earliest figure of art rock has been assumed to be record producer and songwriter Phil Spector, who became known as an auteur for his Wall of Sound productions that aspired to a "classical grandiosity". According to biographer Richard Williams: " created a new concept: the producer as overall director of the creative process, from beginning to end. He took control of everything, he picked the artists, wrote or chose the material, supervised the arrangements, told the singers how to phrase, masterminded all phases of the recording process with the most painful attention to detail, and released the result on his own label." Williams also says that Spector transformed rock music as a performing art into an art that could only exist in the recording studio, which "paved the way for art rock".