For many people, the sound of America's bluegrass evokes one of two images. People either think of that “Dueling Banjos” scene and the darker connotations that come with the backwoods creepiness of John Boorman's “Deliverance,” or you go with the fun, narrative-supporting soundtrack of the Coen brothers' sly comedic odyssey, “O Brother, Where Art Thou?” Looking to promote the latter's far more appealing image, the Science Museum of Virginia hosts City Slickers: Richmond's Bluegrass Festival on Saturday, May 9 at 3 p.m. The festival features a mixture of string-based talent from the Grascals, the Seldom Scene and the teenage mandolin protAcgAce Sierra Hull (pictured). Call 800-594-8499 or visit www.cityslickers.tickets.musictoday.com. $15-$20.