Physics
Head-Related Transfer Function (HRTF)
Quick fact
Your HRTF is unique—like a fingerprint for your ears. The shape of your head, ears, and even your shoulders creates a personal sound filter that your brain uses to judge direction.
Why this is interesting
Have you ever closed your eyes and known exactly where a sound is coming from? Your brain uses tiny differences in sound arrival time and loudness between your ears—but that's only part of the story.