Old school but never old, Boulder Acoustic Society is the new wave of American roots music. It’s what happens when four songwriters get together to mash up blues, folk, gospel, indie and world music to soothe their musical curiosity. The energy that B.A.S. brings to a stage can tip a festival into overdrive or mesmerize a club audience as they dance into the wee hours. All of this comes from four guys who wear vintage clothes, savor small batch bourbon and rock the ukulele. Boulder Acoustic Society is coming Wednesday August 5 at 7:30 p.m. Woodmen Hall. $10. More info: http://www.homeonthegrange.com 468-2753