A=Import["harddaysnight.wav"]; L=A[[1,1,1]]; R=A[[1,1,2]];Now L are the sampled values of the left sound track.

An article in the german "Spiegel" talks about
Jason Brown who uses mathematics
to analyze music, like the work of the Beatles.
Here is an article of Brown.
You can do this yourself, for example with Mathematica. Here are the first 6 seconds of the song
"Hard days night" in Wav format. And here is how you
can import that into Mathematica:
And here is the Spiegel article:

A=Import["harddaysnight.wav"]; L=A[[1,1,1]]; R=A[[1,1,2]];Now L are the sampled values of the left sound track.