Curious. Back in the stone ages (12 years ago) we had a 53 GB 12-platter drive (The box said "Solve your disk space storage problems forever!") that had a head fail. I was able to recover 22/23rds of the data, but it was clear that the data was recorded from one platter to the next all the way through the stack, and then the heads moved. Back in that day (I don't know if it's still true) one side of one of the platters just contained alignment information.
We have two ears, but you might notice that the ears have fairly complicated geometry. Why would that be? Well, it turns out that the various parts of the ear bounce sound, and sound coming from different directions, both azimuth and elevation, bounces differently. Your brain is very good at figuring this out. This wikipedia page on Sound Localization is quite informative.
It turns out that humans have among the best direction-sensing hearing of any animal.
[disclaimer -- I work for Dolby, but in their imaging group]
I'm not all that fond of phone based two-factor authentication any way. Especially, because phones break, get lost or get stolen at the least opportune moments.