That's devestating; as I fumbled my way through learning bass by picking up stuff from albums, his work with Canned Heat and Mayall was go-to material. Rarely do you see someone have such a good time playing bass on stage...
Some time back, I had the privilege of meeting him through a CL transaction; he had long since given up electric, and was playing upright exclusively with Tom Waits. He had been given a bunch of combo bass amps in the UK(as a potential endorsement deal), and was selling them off in an anonymous ad. I went out to his place out in the Valley, and as I was trying the amps out, through random conversation, it finally struck me who this guy was. It was all I could do to keep from being a gibbering fan boy. He was telling me about a joint Dylan/Waits tour, invited me into the house to see some memorabilia, and so on, a magical afternoon.