[boxcardavin]

Localizing the sound isn't just a matter of hearing a phase shift between your ears, you also have some 'knowledge' about how sound moves in a room, how your ears change the sound, and what frequencies will be more prominent given which side of you the sound is made on. The human brain kills it at real time signal processing.

[mediaman]

I read somewhere that the human (and ape) ear has evolved its unique set of grooves and folds to help create sound reflections that allow the brain to better spatially locate sound, even without phase shifting between both ears.

This also allows us to locate sound not only spatially along the axis between the ears, but above and below as well.

I wonder if people using hearing aides, where the sound is recreated further inside the ear, are less able to locate sound sources.