Noise Cancelling Headphones - The basic principles of How They Block Unwanted Noise2573035

You can find basically two types of headphones created to reduce background noise. Passive noise cancelling headphones and remove background noise from video app. The passive type muffles extraneous sounds even though the active ones electronically decrease external noise.

Passive-

Passive noise cancelling headsets use what is called circum-aural sound dampening design. They're shaped like a cup, which surrounds the ear. The rim with this cup is made 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 than the passive type. It employs the identical technology (circum-aural sound dampening design) since the passive headphones but in addition incorporates phase cancellation. This is actually the key feature of active noise cancelling headphones. A microphone is put inside the headphone that picks up external noise that the aural cushions of the passive headphones are unable to block out. The phase cancelling technology is able to analyze the intensity and frequency of the pitch, also referred to as the loudness and pitch with the noise. The circuitry then creates a perfect replica of 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" together with whatever it is that you are listening to. This artificial noise is the exact opposite with the extraneous noise that means it is 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, enabling you to enjoy your audio using a dramatic decline in background noise.

These types of headphones are ideal for airplanes or anywhere where there is much external noise. On airplanes, for instance, this type of noise reduction while using headphones will dramatically reduce fatigue.

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

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