At this point in time, The Beatles had completed two versions of “Strawberry Fields Forever”: the original recorded by the core band, and the rerecording augmented with cellos and trumpets. Unable to make up his mind which he preferred, John Lennon was suddenly struck with a brilliant — if impractical — idea.

Lennon, history tells us, was not technical-minded, and often not interested in the piddling details of how something was going to be accomplished. He knew what he wanted, and would leave the rest up to the George Martins of the world. In his book All You Need Is Ears, Martin says that his conversation with John about “Strawberry Fields” went like this:

John: I like the beginning of the first one, and I like the end of the second one. Why don’t we just join them together?

George: Well, there are only two things against it. One is that they’re in different keys. The other is that they’re in different tempos.

John: Yeah, but you can do something about it, I know. You can fix it, George.

So today George Martin and engineer Geoff Emerick set about trying to make John’s vision a reality. According to The Beatles Bible, the first recording was in A major and the second was in C. By speeding up the first and slowing down the second, Martin and Emerick created a hybrid in the neighborhood of B flat. This is the “Strawberry Fields Forever” that we’ve been listening to for nigh on 50 years now, and that is playing in my living room at this very moment. There are many different versions, I think, in many different universes, but I’m reasonably pleased with ours. That is, I think it’s not too bad.