Your brain has various ways of detecting where a sound is coming from, but the main one uses the fact that you have two ears (known as binaural hearing). Sound travels at about 330m/s which means that if there is something noisy to your left, the sound will get to your left ear about a 2000th of a second before it arrives at your right ear. This means that the signal will get to your brain this much sooner, and so your brain can calculate that the source of the sound is to your left.
Similarly, if the object is to the right, the sound will get to your right ear first.
The sound reaches your left ear first, so the signal from that ear gets to your brain first, and your brain knows the sound is coming from the left.
Now the sound reaches your right ear first, so your brain knows the sound is coming from the right.
The funnels are good at collecting sound and ‘funneling’ it into the tubes – so most of the sound that gets to your ears has come through the tubes.
If a noise is on the left hand side, the sound reaches the left hand funnel before the right. It then travels through the tubes and gets to your right ear before your left, so your brain interprets this as sound coming from the right – as a result, you get very confused!