Noise Cancelling Headphones - The Basics of How They Block Unwanted Noise3113726

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

Passive-

Passive noise cancelling headsets use what is known as circum-aural sound dampening design. They're shaped like just one cup, which surrounds the ear. The rim of this cup is constructed of a high-density foam and sound wave dampening material. This results in a seal that blocks as much as 20 dB of noise.

Active-

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

The headphone speaker then plays this "non-sound" along with whatever it is that you are listening to. This artificial noise is the exact opposite from the extraneous noise that makes it past the ear cushions. They then cancel each other out due to the 180-degree phase reversal. Consequently the external noise is reduced significantly, enabling you to enjoy your audio using a dramatic reduction in background noise.

These kinds of headphones are ideal for airplanes or anyplace where there is a lot of external noise. On airplanes, for instance, this type of noise reduction with all the headphones will dramatically reduce fatigue.

Another distinction between the two is the active type takes a power source, often a battery.

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