I have always loved this:
David Freiberg from Quicksilver Messenger Service, with an awesome bass solo.
Taken from the "Who Do You Love" Suite, Part 5 - "Which Do You Love"...
From the album "Happy Trails", Recorded live in 1969 at the Fillmore, both East and West. (NY & SF).
Here's the full "Who Do You Love" suite, at 25 minutes long.
Well worth a listen if you like psychedelic rock, John Cippolina, or the San Francisco sound.
Freibergs bass is very prominent in the whole recording, and I personally think he's one of the best bass players, past or present.
He's still actively playing with Jefferson Starship and the Linda Imperial Band. Linda Imperial also happens to be his wife.
He was also one of the only SF musicians to be a member of QMS, Jefferson Airplane
and Jefferson Starship. He also occasionally collaborated with the Grateful Dead members on side projects.