I have a right and left ear, so I get how I can tell if a sound comes from my right or left. How can my 2 ears tell me if a sound is coming from in front of me, behind me, above me or below me?
In: 2
Sound localisation comes down to a few factors
1) Sound travels at about 330m/s in air at normal atmospheric conditions*. This means that if a sound is coming from one side or another, there will be a small difference. .6ms or something, it’s tiny, but your brain uses this information. This gives horizontal plane information, A sound directly in front, above, behind… will reach each ear simultaneously though.
2) Your head casts a ‘shadow’. About 40dB in the high frequencies is blocked by your big old noggin. Your brain also uses this difference to calculate location. Again, this is horizontal information though. We know which side it is coming from, but not its height.
3) The shape of your outer ear (the pinna) and ear canal have a load of turns and bends, this actually affects the way sound travels, affecting sounds coming in from different directions in different ways. Your brain uses these subtle changes to calculate vertical direction.
*so to count how far lightning is and listening for thunder, every 3secs is 1km
Latest Answers