Is there a Southern-rock revival afoot in the mainstream? The success of acts like the Zac Brown Band points to yes. That group's bridging of the market gaps between the rock and country crowds has paved the way for similarly swampy acts, among them close pals Blackberry Smoke. The Atlanta-based quintet isn't a new act by any means. Led by lead vocalist/guitarist Charlie Starr, the group's been plying its bearded trade for more than a decade. But in a landscape of overly compressed and formulaic guitar tunes, the group sounds fresh. Yes, this is "Southern rock," but Southern rock encompassing all the great musical traditions of the South — swamp boogie, bluegrass, rock, country, and even backwoods gospel. Come testify this Wednesday at Revolution, where opening support is provided by the similarly multifaceted local act the Jacob Jeffries Band.