A home recording by Jimi Hendrix, which its owners said showed the 1960s rock icon's softer side, will be auctioned next month and is expected to fetch between $70 to 140,000.
According to co-owner Mark Sutherland, the tape was recorded by Hendrix in New York in 1968 and then taken to Britain.
Carl Niekirk worked in a photography studio below Hendrix's central London residence where, because there was only one entrance to the building, he often doubled as doorman for his famous neighbor, letting in guests including George Harrison.
"I don't know how the tapes got from New York to London, but they must have been important if he took them with him," Sutherland said.
"Hendrix ended up in London above where Carl worked. Carl kept getting disturbed by people, and said 'a favor for a favor' ... and Jimi gave him two tapes."
Sutherland said a friend met Niekirk in a pub several years ago and bought the tape from him "for a nominal fee." He is not sure what happened to the second recording.
Since then the tape's new owners have been in legal dispute with the Hendrix estate, and Sutherland said he was now finally able to auction it. Hendrix's estate was not immediately available for comment.
Sutherland and Ted Owen, managing director of pop memorabilia auctioneer the Fame Bureau which is handling the April 28 online auction, are confident the tape is genuine.
"It's pretty obvious," Owen told Reuters. "I have listened to nearly every outtake of Jimi Hendrix and am very familiar with the personal reels. Thirty seven are known to exist, but now only one is out there in the public domain."
Sutherland said the tape featured 14 tracks, including Hendrix performing Bob Dylan track "Tears of Rage." Hendrix famously covered Dylan with "All Along the Watchtower."
"His playing is unique but there are a lot of Hendrix clones," said Sutherland, who is a record producer.
"As soon as he started singing, though, that was it. There is a Dylan song on there in an acoustic and folksy-type style that no-one's heard. It is away from Jimi's wildness and blues."
The tape includes tracks from the 1968 album "Electric Ladyland" and features Hendrix singing and playing the guitar as well as an unidentified harmonica player.
Interest in Hendrix memorabilia has been high in recent years. In September the first guitar to be set alight by Hendrix on stage fetched 280,000 pounds at a Fame Bureau auction.
Hendrix is considered one of rock's greatest guitarists and showmen and a pioneer of the psychedelic music scene. He died in London in 1970 aged 27. | 
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