Sir Paul McCartney was amazed by his wife HEATHER's ignorance of his musical achievements.

Heather, 37, wasn't born when THE Beatles were at their peak, but McCartney, 63, still expected her to have heard of his songs.

He tells the New York Daily News, "Once GET BACK was playing somewhere. She sort of recognised my voice and said, 'Is this you?' I said, 'Yes, darling. It's called Get Back. It's quite famous.'"