Tony Visconti has described David Bowie's 'Toy' as a "ghost album".
The previously unheard collection - which was recorded in 2001 and will finally get an official release next month as part of the 'Brilliant Adventure (1992–2001)' boxset - features three new songs as well as new versions of some of the late legend's early material.
Reflecting on the record, Visconti told Uncut magazine: "Some of them were so old they dated even before my time with him. I think many artists would love to go back and remake certain albums.
"This gave David the perfect opportunity to rework those old songs, which, from the beginning, proved that he was always a great songwriter.
"It meant he could go back and shine a light on his earlier stuff. It's a bit of a ghost album, it's a transitional album.
"And I'm so glad people are now getting to hear it, because I think some of David's finest work is on 'Toy.' "
The 77-year-old producer first worked with Bowie on his 1968 single 'In the Heat of the Morning' / 'London Bye Ta-Ta', and their working partnership continued until 1980's 'Scary Monsters (And Super Creeps)'.
They had originally discussed reuniting in 1999, but getting back in the studio for 'Toy' marked the first time they'd worked together in a long time.
He explained: "We hadn't spoken to each other for a long time. I got a call from someone, saying that David was trying to contact me.
"It was like, 'He wants to know if you're friendly' or 'mentally competent', something like that. I don't know, it was a weird message.
"This was the beginning of David and I working together again, until the day he died. I was a trusted friend and we had a method of communication that was near-on telepathic. It was as natural as putting your shoes on in the morning."