Doug Fieger, lead singer of rock group the Knack, died at 57 after a battle with cancer, his brother Geoffrey confirmed today. “I’ve had 10 great lives,” Fieger told the Detroit News in a January interview. “And I expect to have some more. I don’t feel cheated in any way, shape or form.” Get the Knack, the album that featured “My Sharona,” spent six weeks at No. 1 in 1979.