A copy of the first demo ever recorded by the Doors is headed for a Heritage Auctions sale later this month.
The highly rare acetate is expected to sell for more than $25,000 when it hits the auction block in Beverly Hills, as part of the company's Entertainment & Music Memorabilia auction on June 24-25.
Described as "the holy grail for Doors collectors", just five original copies of the acetate are known to exist.
The demo was recorded in September 1965, and features early versions of six songs including Hello, I Love You, which later sold more than a million copies in the US alone.
The session at World Pacific Studios in Los Angeles had originally been booked by keyboard player Ray Manzarek for his first band, Rick & the Ravens.
But after meeting Jim Morrison, and recruiting drummer John Densmore from local band the Psychedelic Rangers, the band hit the studio as the Doors for the first time.
The original line-up also included Manzarek's two brothers Rick and Jim, along with a session bass player Patty Sullivan, before later slimming down to a four-piece with guitarist Robby Krieger.
Although Morrison's vocals have yet to develop a confidant swagger, and Manzarek hasn't yet plugged in his electric organ, the demo still sounds like the Doors we know today.
The six-track demo was widely bootlegged for years, before being officially remastered and released in 1997 using Manzarek's personal copy of the acetate.
It's believed the copy offered at Heritage was last sold on eBay back in 2011 for $3,650, but its rarity has seen it soar in value, and the estimate of $25,000+ would mark a significant increase in the space of just five years.
Memorabilia from the Doors, and Jim Morrison in particular, remains highly sought-after with collectors; in 2013 a notebook full of poems he wrote in the final weeks of his life sold at auction for $200,000.
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