It took a mathematician:
Four years ago, inspired by reading news coverage about the song’s 40th
anniversary, Jason Brown of Dalhousie’s Department of Mathematics
decided to try and see if he could apply a mathematical calculation
known as Fourier transform to solve the Beatles’ riddle. The process allowed him to decompose the
sound into its original frequencies using computer software and parse
out which notes were on the record.
It worked, to a point: the frequencies he found didn’t match the known
instrumentation on the song. “George played a 12-string Rickenbacker,
Lennon had his six string, Paul had his bass…none of them quite fit
what I found,” he explains. “Then the solution hit me: it wasn’t just
those instruments. There was a piano in there as well, and that
accounted for the problematic frequencies.”