It Only Took Black Sabbath One Week to Change the Sound of Rock

In 1970, just months after their debut album had been released, four lads from Birmingham re-entered the studio to record a follow-up. It took them less than a week, but its impact would be eternal, helping to create a new sound in rock that would come to be called "heavy metal." Randy Renaud looks back at the creation of the Black Sabbath masterpiece, Paranoid, in honour of the band's farewell concert in Birmingham.