Noise Cancelling Headphones - The Basics of How They Block Unwanted Noise7492604

You can find basically two kinds of headphones created to reduce background noise. Passive noise cancelling headphones and background noise reduction. The passive type muffles extraneous sounds while the active ones electronically decrease external noise.

Passive-

Passive noise cancelling headsets use what is known circum-aural sound dampening design. They are shaped like a cup, which surrounds the ear. The rim of the cup consists of a high-density foam and sound wave dampening material. This creates a seal that blocks up to 20 dB of noise.

Active-

The active noise cancellation headphones produce an additional 20dB of noise reduction compared to passive type. It employs the identical technology (circum-aural sound dampening design) since the passive headphones but additionally incorporates phase cancellation. This is the key feature of active noise cancelling headphones. A microphone is positioned inside the headphone that accumulates external noise the aural cushions with the passive headphones are unable to block out. The phase cancelling technology is able to analyze the intensity and frequency with the pitch, also known as the loudness and pitch of the noise. The circuitry then creates an exact replica from the noise and throws it 180 degrees out-of-phase. This, for those intents and purposes, eliminates the sound.

The headphone speaker then plays this "non-sound" in addition to whatever it is that you're listening to. This artificial noise may be the exact opposite from the extraneous noise which makes it past the ear cushions. Then they cancel one another out due to the 180-degree phase reversal. As a result the external noise is reduced significantly, letting you enjoy your audio using a dramatic reduction in background noise.

These kinds of headphones are fantastic for airplanes or anywhere where there is much external noise. On airplanes, for example, this type of noise reduction with all the headphones will dramatically reduce fatigue.

Another difference between the two is the active type needs a power source, usually a battery.

Noise cancelling headphones are usually larger and heavier that regular headsets or earphones. They are able to, however, become more comfortable when worn for very long periods of time due to the large cushions that impose less pressure around the ears.