Aretha Franklin's funeral service on Friday in Detroit was an extraordinary occasion by every measure as family, friends, civil rights activists, preachers, and a former president celebrated the Queen of Soul. And the undercurrent to it all was music. All kinds of musicians were at the Greater Grace Temple to pay tribute to a legend and the raw power of her music. Some of the performers, including Stevie Wonder, counted Aretha Franklin as a friend and colleague for many decades.