The lean, mean, down-in-the-groove power trio Boku Frequency has been performing in Duluth for about 20 years. Longtime members Thomas Harris and Terry Gums were joined by drummer Rick Bruner about four years ago. When they combine their own styles with influences including James Brown, Jimi Hendrix, Isaac Hayes, War, Sly and the Family Stone, Santana, the Isley Brothers, and a whole lot of other 1960s and ’70s powerhouses, the sound comes out as psychedelic Duluth funk rock.