The ‘new’ Beatles song is perfectly fine. That’s not good enough.

One day in the late 1970s, John Lennon hit the record button on a boombox at his Upper West Side co-op and sang a new song he had been working on, accompanying himself on piano.

For decades, his Beatles songwriting partner Paul McCartney yearned to transform this raw solo demo into a studio-polished collaboration that could properly serve as the Fab Four’s final song. Finally, some 45 years later, the technology arrived that would free Lennon’s voice from its sonic trap of atmospheric hum and tinny piano so they could blend it seamlessly with his surviving bandmates’ fresh vocals and instruments.