Cox remained in touch with Hendrix as the guitarist rose to fame. When Hendrix split with bassist Noel Redding in 1969, the guitarist called on Cox to be his new bassist.
The first major gig that Cox played with Hendrix was Woodstock in 1969. Cox remembers the feeling of amazement that he, Hendrix and drummer Mitch Mitchell felt when they first saw the size of the crowd from a room in a loft on the festival grounds.
“Jimi pulled the curtain back and looked, and his eyes were big as quarters,” Cox said. “But in his wisdom, he said, ‘You know what, these people are sending a lot of energy up to the bandstand. So what we’re going to do is we’re going to take that energy, absorb it musically and send it right back to them.’ We went out and we stayed onstage almost two hours, I think an hour and maybe 48, 51 minutes or something of that nature. And that’s what we did. We took that energy and sent it right back to the crowd. And it was incredible.”
In the studio, Cox played numerous songs that Hendrix recorded up to his death on Sept. 18, 1970. Some of those songs grew from riffs and ideas they had explored together after the Army. Cox remembers what Hendrix said back then.
“A lot of times, we’d be eating strawberry upside-down cake and Coke or whatever, and he’d look at me and he’d say, ‘You know, if we put this on wax, on a record, they would lock us up,’ because I think it was so far ahead of its time,” Cox said. “So when he called me in (in 1969), he said, ‘You remember some of that stuff?’ I said, ‘I remember all of that stuff.’ I played it for my own amusement. Therefore, you got songs like ‘In From the Storm,’ ‘Dolly Dagger,’ ‘Freedom,’ songs of that nature that we put together from these riffs that we used to play with all the time.”