Apparently our brains, or at least the one that belongs to Oliver Sacks, can distinguish subtle differences in music, even when the conscious mind cannot. In an MRI, Oliver’s brain showed more activity when listening to Bach (his favorite composer) than when listening to Beethoven. This occurred even when Oliver was unable to tell which piece was Bach and which was Beethoven. Sorry Ludwig.
I’d be interested to see what this experiment would reveal with additional test subjects and varied composer preferences. Check out the ~4 minute Nova video.