Richie Havens was the perfect African American folkie for the 60s counterculture: he was gritty (and sexy) enough to be deemed authentic, topical enough to satisfy the obligatory "relevance" criteria of the times, and nonthreatening enough to be palatable to middle-class revolutionary wannabes. From anthemic chants like "Freedom" to introspective takes on Bob Dylan's "Just Like a Woman" and Van Morrison's "Tupelo Honey," Havens fused liberation politics with a hip, vaguely psychedelic romanticism. The sound he created to convey his message was a unique and captivating blend of multilayered rhythms, hypnotic open-guitar tunings, and a dusky vocal timbre. Thirty years later his music remains determinedly optimistic and he's as righteous as ever: he channels his offstage energies into organizing children's crusades for the environment and still shows up for every benefit concert he can pack into his schedule. Now if he'd only tell us why he let them use his version of Dylan's "The Times They Are A-Changin'" as the sound track on a recent TV commercial for an investment firm . . . Saturday, 7 and 10 PM, Old Town School of Folk Music, 909 W. Armitage; 525-7793.