THE SUN is going down on Memphis, site of rock’n’roll’s immaculate conception and explosive birth. On a warm spring evening, the Mississippi’s purplish-brown waters are swirling and eddying beside us. In the distance loom the empty towers of the city’s devastated downtown centre. People drift into a performance area demarcated as "The Budweiser Stage", one of several set up for this weekend’s annual Memphis In May music festival.