Exclusive: Listen to one of Jimi Hendrix's last songs with the Experience

Get ready to hear another side of Jimi Hendrix. 

The legendary guitarist is being memorialized on Both Sides of the Sky (out March 9), which features 13 studio recordings he made between 1968 and 1970 — 10 of which have never before released. A freewheeling, never-before-heard rendition of Hear My Train A Comin', recorded in New York in April 1969, is premiering exclusively on usatoday.com. 

First recorded in 1967 in London, Hear My Train was an original blues composition inspired in part by Hendrix's childhood hero, Muddy Waters. It was also a concert staple for him and his band, the Experience: bassist Noel Redding and drummer Mitch Mitchell. 

But what makes this version of Hear My Train unique is that it's one of the last songs the Experience recorded together, amid simmering tensions between Redding and Hendrix. 

"There was an undercurrent of Noel wanting to be a solo artist and be recognized on his own," says John McDermott, a Hendrix historian who co-produced the album. "But when they put their focus together on a song or a concert, they had a tremendous chemistry. It's evident to anybody."

The unease was palpable in the Record Plant studio that day, and manifested in more than seven minutes of electrifying riffs on the extended Hear My Train. 

"What I love about this is you got Noel pretty much driving the band, because I think he's aware that he's out," says Eddie Kramer, a recording engineer who worked on all of Hendrix's records until the artist's death in 1970 at age 27. "You've got three musicians in the studio, a little bit of angst and the bass player pushing up against Jimi — it yielded a magnificent take." 

But not every track on Both Sides was done in such tempestuous conditions. A previously unreleased take on Lover Man, for instance, was recorded in December 1969 with Hendrix's new group, Band of Gypsys, featuring bassist Billy Cox and drummer Buddy Miles.  His bandmates were spent after nearly two dozen takes, so Hendrix decided to lighten the mood by interpolating TV themes into the song. 

"The guys in the band just cracked up," Kramer says. "He made it very loose and very cool, just to get everybody to relax." 

Adds Janie Hendrix, the rocker's sister: "People have often asked the question, 'What was Jimi really like?' Jimi had a great sense of humor. In Lover Man, he used a little bit of Batman and a little bit of Peter Gunn, which is one of the first songs he ever learned to play. Also, on Stepping Stone, he does this sort of 'neener neener neener,' which is what kids will do when they're playing tag and having fun. You hear the versatility of his playing and very blues-oriented songs, but songs that are done in a lighthearted way as well. They're just jamming and having fun."

Other noteworthy creations on Both Sides include Woodstock, which was written by Joni Mitchell and finds Hendrix jumping on bass opposite Stephen Stills (of Crosby, Stills, Nash & Young); Cherokee Mist, in which he plays electric guitar and sitar; and Things I Used to Do, which can be heard in full for the first time. 

The album is the third in a trilogy of posthumous releases remastered by Kramer, McDermott and Hendrix's sister, after 2010's Valleys of Neptune and 2013's People, Hell and Angels. Next, they're digging deeper into the family archives for a new documentary based around Hendrix's appearance in out-there 1971 film Rainbow Bridge. 

"It's an honor to be able to continue his mission in life, which was for people to be able to hear his music," Janie says. "When I was 6 — and Jimi is 18 years older than me — we both made a promise to always take care of each other. I, at 6 years old, thought he would still be here.

"My dream was always to be a part of his music history and legacy, and to be able to do that is the best gig to have," she adds. "People continue to hear his music fresh and versions they hadn't heard before. It's about educating the public: not just the generations that may have experienced his music in a concert form, but also young kids coming up and learning real music."