John Cowan

As the bassist and vocalist for the New Grass Revival in the ’70s and ’80s, John Cowan helped expand the scope of bluegrass music, playing heavier and flashier than the genre’s forefathers, and also dabbling in then-blasphemous covers of songs by The Beatles and Bob Marley. Of course, Cowan has plenty of company these days, thanks to the young, freewheeling “jam-grass” scene, but he was among the first to take a gamble on pairing the sounds of Bill Monroe with the pomp and energy of Led Zeppelin, honing a style of progressive bluegrass that he has continued to explore on his recent solo albums. Cowan plays a 9:30 p.m. show at Vnuk’s Lounge tonight.