Sound waves pass through this microphone and are amplified, allowing the listener on the other end to receive clearer audio. Without the secondary microphone, call quality would significantly decrease.
Most mobile phones today have two noise-reducing microphones, one at the top and one at the bottom. When the phone is affected by environmental noise, the secondary microphone reduces this noise, leaving only the call’s audio. This technology, known as “dual microphone noise reduction,” makes calls clearer even in noisy environments.