Paul McCartney says recording his latest album, a back-to-basics rock 'n' roll collection called Run Devil Run, was a theraputic exercise after the death of his wife Linda.
It was Linda, who died last year from breast cancer, who inspired the album and urged him to record it.
He says playing the music took him back to the more carefree days of his early career.
"I'd often talked to Linda about it," he recalls.
"She loved her rock 'n' roll. She was an original doo-wop fan."
"She was always saying to me, 'You've got to do this, you've got to do this'", McCartney says.
"So it was coming to the end of the millenium and I decided 'I've got to do it.'"
"I thought it might have a theraputic effect by taking me back to the old days and making me feel good. That's exactly what it's done."
He says the album had "none of this modern overdubbing stuff", just plain "old fashioned music the way we made the original Beatles albums".