Thanksgiving Day afternoon, and I've watched zero television. Right now, I'm listening to Grace Slick and the Great Society. For you young'ns, that's the band Grace was in before Jefferson Airplane, which was before Jefferson Starship. It's been a Grace Slick-athon for most of the early afternoon.
This proports to be from the last performance by the Jefferson Airplane's lead singer, Signe Toly Anderson, with her signature song, "Chauffer Blues." There is an album that was released in 2010 called Jefferson Airplane: Live at The Fillmore Auditorium 10/15/66 Signe's Farewell. According to Wikipedia, she sang this and an encore, and the next night, the band performed with Grace Slick; not missing a beat. I haven't listened to enough of Signe to tell if her overall style is similar to Grace's, but at least in this song it is.
The album "Jefferson Airplane Takes Off," with founding member, lead singer Signe Toly Anderson.