Humans are actually relatively inept at locating sound sources. For low frequencies, the main cue is phase differences. At high frequencies, your head is a few wavelengths wide, and this doesn't work, so the systems shifts to a time-of-arrival mode. This is much trickier, as you have to a) get another sample after mode switching, b) you only get one edge per sound, and c) if the sound doesn't have a sharp attack, it's hard to pin down the edge. The last effect is magnified by the fact that it takes a little while for human ears to detect a quiet, high frequency signal, effectively destroying the sharp attack. There is a third method, based on differential frequency amplitude and phase, which depends on the convolutions in the external ear to form a filter that encodes angular information (this is the sole method for hearing elevation as opposed to azimuth differences).
Cats have us utterly whipped on all of the above, even before their incredibly useful independently rotatable pinnae (which also need a second sample to get aligned and useful). I've often used my cat to pinpoint sounds for me -- even a tiny little wheep will normally be noticed and localized. You can read off three indicators (each ear and the direction of gaze) -- however it's up to you to determine which reading is applicable for the sound you currently find interesting (the cat will have her own opinion of what is and is not interesting). And it's possible the cat will have already investigated and dismissed the sound you're after. It is possible to communicate to a cat that there is a sound you'd like to know more about, and some cats are willing to help out here (they're quite aware that we're bumbling fools when it comes to hunting). However I can't do this reliably, or explain how it's done, just relate that I have managed to encourage cats to tell me where the blasted noise is coming from. This trick is much easier with dogs, but I don't usually live with dogs.
sound location
the main cue is phase differences.
At high frequencies, your head is a few wavelengths wide, and this doesn't work,
so the systems shifts to a time-of-arrival mode.
This is much trickier, as you have to a) get another sample after mode switching,
b) you only get one edge per sound, and c) if the sound doesn't have a sharp
attack, it's hard to pin down the edge. The last effect is magnified by the fact
that it takes a little while for human ears to detect a quiet, high frequency signal,
effectively destroying the sharp attack.
There is a third method, based on differential frequency amplitude and phase,
which depends on the convolutions in the external ear to form a filter that encodes
angular information (this is the sole method for hearing elevation as opposed to
azimuth differences).
Cats have us utterly whipped on all of the above, even before their incredibly useful
independently rotatable pinnae (which also need a second sample to get aligned and
useful). I've often used my cat to pinpoint sounds for me -- even a tiny little wheep
will normally be noticed and localized. You can read off three indicators (each ear
and the direction of gaze) -- however it's up to you to determine which reading is
applicable for the sound you currently find interesting (the cat will have her own
opinion of what is and is not interesting). And it's possible the cat will have already
investigated and dismissed the sound you're after. It is possible to communicate
to a cat that there is a sound you'd like to know more about, and some cats are
willing to help out here (they're quite aware that we're bumbling fools when it comes
to hunting). However I can't do this reliably, or explain how it's done, just relate that
I have managed to encourage cats to tell me where the blasted noise is coming from.
This trick is much easier with dogs, but I don't usually live with dogs.