We need two ears...

Our two ears act like radar antenna to register acoustic signals coming from multiple directions. The complex structures of each ear process the received signals and pass them to the brain where we interpret our acoustic environment.

Take, for example, the sound of an approaching truck: the nearest ear receives the sound slightly earlier than the other and a little louder. Using the finely processed acoustic information from each ear, the brain has the capacity to calculate the direction of the truck's approach and we also "know" approximately how close it is.

Some of the advantages of two properly functioning ears:

• excellent sound localization skills
• much easier speech understanding in noisy situations
• the richest sound quality
• an accurate judgement of loudness