What are Noise Cancelling Headphones?
“Large circumaural headphones enclose the wearer’s ear for superior noise cancellation. Noise-cancelling headphones reduce unwanted ambient sounds (i.e., acoustic noise) by means of active noise control (ANC). Essentially, this involves using a microphone, placed near the ear, and electronic circuitry which generates an “antinoise” sound wave with the opposite polarity of the sound wave arriving at the microphone. This results in destructive interference, which cancels out the noise within the enclosed volume of the headphone. Noise cancellation makes it possible to enjoy music without raising the volume excessively. It can also help a passenger sleep in a noisy vehicle such as an airliner. Source: wikipedia.org Personal Noise Pollution at the Human Level Environmental noise is unwanted and displeasing sound that disrupts the mental process, activity or quality of human life. This noise pollution comes from many sources including: barking dogs, car alarms, office noise, noisy people, t
