Behind those gigs is the story of the man Hendrix leaned on as a friend and musical collaborator. Onstage with Hendrix during his first serious gigs and his last performances, Cox’s low-end support aptly complemented Hendrix’s guitar stratospherics. “A bloody marvelous bass player—has soul and feel for days,” notes Hendrix engineer Eddie Kramer. “He was Jimi’s confidante and buddy—and a wonderful human being.”

Cox’s story starts in Wheeling, West Virginia, where he was born, and then moves to Pittsburgh, where he grew up. Music was always in the house. Young Billy learned to play a number of instruments, but he didn’t find his musical home until one summer day before his senior high-school year: “They were having a dance that afternoon, and I heard a low sound resounding in the universe—it was electric bass. I knew that instrument was going to be the key to my musical future.”

Soon afterward, Cox went into the Army and joined the 101st Airborne at Fort Campbell, Kentucky. That’s where he first heard Private Jimmy Hendrix playing guitar inside a service club. “He was out of tune, but I heard something in there,” Billy recalls. “I said, “Man, that cat is going to be bad.” Cox—at first playing an Army-issue Danelectro and later a P-Bass—was soon jamming with Hendrix and gigging at the base and in nearby Clarksville, Tennessee. Leaving the service about the same time, the two headed down Highway 41 to Nashville, where their band, the King Kasuals, got work in clubs like Del Morocco and Jolly Rogers, and then on the chitlin circuit. It wasn’t long before Hendrix was touring nationally with acts such as the Isley Brothers, while the less-adventurous Cox stayed behind. “He finally joined Little Richard and decided to go to New York,” Billy says. “He called me and said, ‘Hey, man, this guy’s discovered me and is going to take me to Europe and make me a star.’ I said, ‘I can’t go anywhere.’” So he said, “Okay, I’ll make it, and I’ll send for you.’ And that’s what he did.”

As promised, “this guy”—Animals bassist Chas Chandler—took Hendrix to London, where they assembled the Jimi Hendrix Experience. For the bass spot they enlisted guitarist Noel Redding, with drummer Mitch Mitchell completing the trio that would record three albums that redefined rock music and rock guitar: Are You Experienced, Axis: Bold as Love, and Electric Ladyland.

Back in Nashville, Cox was gigging and doing studio work, especially gospel sessions for the Excello label. He also played in the house bands for two legendary R&B TV shows: Noble Blackwell’s Night Train and Hoss Allen’s Dallas-based The!!!!Beat. Finally, in April 1969—with the original Experience falling apart—Hendrix called on his old friend to help him salvage foundering sessions at New York’s Record Plant. Cox joined Jimi in the studio, working on riff-based songs for which they’d laid the groundwork in their earliest jams. Cox also played with Hendrix that August at the Woodstock Music & Art Fair with an expanded band billed as Gypsy Sun & Rainbows.

In late 1969 drummer Buddy Miles replaced Mitchell, working in the studio and joining Hendrix and Cox for a New Year’s Eve performance at the Fillmore East. The resulting live album, Band Of Gypsys, shows the guitarist in full creative command and confirming the power of the Cox/Miles rhythm section. Afterward the Gypsys disbanded, and with Mitch Mitchell back on drums, the trio (billed as the Experience) toured and recorded tracks that would be assembled a quarter-century later as First Rays of the New Rising Sun. Mixing Hendrix’s new groove-based style with tunes that recalled the earlier Experience, the album finds Cox leading from the bottom as he locks in with Mitchell’s freewheeling drum approach.

After a string of generally successful U.S. concerts and a trouble-beset European tour anchored by the Isle of Wight festival, Hendrix died of an overdose on September 18 in London, at age 27. Cox would rebuild his career, starting with a tour with the Charlie Daniels Band and a 1971 album, Nitro Function, with singer Char Vinnedge. “I did an awful lot of session work, with knowns and unknowns,” Billy says. “If they needed me to play, I would play. That’s what I do.”

Still living in Nashville, Cox recently teamed with former Band Of Gypsys drummer Buddy Miles and a gaggle of guest guitarists on the CD/DVD The Band Of Gypsys Return, which features both studio and live tracks (including two Cox originals). Billy also gigs under the auspices of Experience Hendrix—the family-run organization that controls Jimi’s legacy—and he also appears at music seminars, rides his Harley-Davidson, and plays “an occasional session.” “I’ve slowed down a little,” he concedes. “I’m in my 60s now and enjoying my life, and thanking the Lord for every day.”

What made you click musically with Jimi Hendrix?
I think it was destiny—we all are destined to do whatever. He looked at me and I looked at him, and it was just like we had known each other for a lifetime. We were the same age, and our influences at that time came from here, in Nashville, out of a 50,000-watt clear-channel station called WLAC. Jimi was in Seattle listening to that, and I was in West Virginia and Pennsylvania listening to it. That was a heavy influence.
Fort Campbell was about 60 miles from Nashville, so naturally we gravitated to that city. But when we came here we found out that it wasn’t what we thought it was. There were opportunities in a lot of small clubs to play blues, but actually it was a country-music town. We played in the black areas and then started going around in the chitlin circuit. These were the little clubs out in the country—on Friday night they had fish and chitlins. Those clubs afforded us the opportunity to have fun and try to make some music.

Did those audiences take to the music you were playing?
Oh, yeah. At that time, we were just trying to get ourselves together. Every now and then we’d throw in one of our instrumentals, and they’d dance to it because they were in a dancing mood. But we didn’t stay out there too long. We stayed with the basics that people understood.

Who were your influences when you were starting out on bass?
Wes Montgomery had a brother named Monk Montgomery. He was incredible for that time on electric bass; I bought everything that Monk Montgomery played on. Then I gravitated to Ray Brown, Charlie Mingus—those were the guys of my time on upright bass. There was also this girl named Carol Kaye who played on [TV’s] Mission: Impossible. I picked up all of her stuff; she was an excellent electric bass player.

What were you and Hendrix playing when you first started jamming together?
Songs of that era—“Green Onions,” “Soul Twist” [King Curtis], Bill Doggett, Bobby Blue Bland—we enjoyed that. Then we would put some things together of our own, but he would look at me and I would look at him, and he’d say, “Man, if we played that they would lock us up.” You can hear remnants of that in songs like “Dolly Dagger” and “In From the Storm.” They were riffs that we liked playing together, sometimes in unison, sometimes in harmony.

It’s interesting that you were working on ideas you would later develop in your New York sessions. Why didn’t you get songwriting credits for any of those tunes?
Jimi died before we put it all together. I did it for the love of the music; I wasn’t looking for any credits. Eventually we were supposed to do that, but it just didn’t happen. I lost my friend.

A lot of the Band Of Gypsys songs are built on tricky bass/guitar unison lines. For the new record did you have to spend time woodshedding them?
“Power of Soul,” “Machine Gun,” “Who Knows”—I was there when that was created. So it’s still in my head, a lot of it. Every now and then I scuff up a bit because I don’t play all the time, but that music will be in my subconscious for the rest of my life.

When you played the Fillmore show that became the Band Of Gypsys album, did you have any idea that the music would make such an impact?
No, but I looked out on the audience during that first show—and when we hit our first note and got into those songs, people were standing there with their mouths wide open. It was funny, the expressions on people’s faces. I think all four of those sets went very, very well. We got enough material and didn’t have to edit anything. We made very few mistakes, and we were feeling it from the head to the toes.

How did you and Miles keep the groove so solid during Hendrix’s long jams?
We would pat our feet and hope we wound up at the same spot at the same time. And it always worked. Jimi and Buddy were excellent musicians, and musicians like that are always going to come in on time.

Buddy Miles and Mitch Mitchell are very different drummers.
I enjoy playing with both of them. What a lot of people forget, when you’ve got good musicians, good musicians jell. Buddy comes from one school, Mitch from another, but each of them is a hell of a drummer. They’re both good—or else they wouldn’t have played with Jimi Hendrix!

Hendrix liked to tune his guitar down a half-step, and on the Band Of Gypsys material you’re tuned down as well.
Jimi liked to sing in Eb, so we would tune down to give him room to sing a little better. And it sounds a little bigger. At the time I asked Jimi, “Why do we tune down?” He said, “There’s only two us, so we can do what we want to do.” A lot times he would be out of tune, and I would say, “Man, you’re out of tune. I guess I am too—I’ll just tune to you.” A lot times we were a whole-step down.

You’ve stated you preferred Marshall amps with Hendrix, though a photo from the Fillmore rehearsal shows you with a stack of various Fender heads and a wall of six Sunn cabinets.
Sometimes we got to pick what we wanted, and sometimes they gave us what they had, whatever was around. A lot of times you might have five cabinets and only one of them was working!

What was it like playing Woodstock?
That was great; it was the first big gig I played with Jimi. We came around the back way and looked out on that crowd—it was the largest crowd I’d ever played in front of. Mitch said, “Hell, I don’t know whether I want to go out there!” Jimi said, “We’ll give to them and they’ll give back to us, and we’ll have a good time.” It was great, it was exhilarating.

Then all of a sudden Jimi starts playing “The Star Spangled Banner.”
If you listen to the recording you hear me playing the first five or six notes. Then I thought, Wait a minute—we never practiced this. So I immediately stepped back, and it was bang—a very great song he did.

In a little over a year Hendrix would be dead. Did you ever say to him, “Hey, man, take it easy with the partying”?
I don’t think it was the partying. It was just … to be. If you look at geniuses like Mozart, they don’t live long. They come to do their thing, and then they’re gone.
I gave a speech at the University of Indiana, and I said, “Every now and then a spirit slips through a portal of time into this reality, and blows our minds.” Jimi’s death devastated me, but then reality kicked in—we all have to do that. I’ll have to make my transition also.

Jimi Hendrix is no longer with us, so all we can do is keep the spirit alive. If you have a dream, follow the dream. It will always work out if you’re sincere.