Noise Cancelling Headphones - The Basics of How They Block Unwanted Noise9690232

There are basically two types of headphones developed to reduce background noise. Passive noise cancelling headphones and Mute Background Noise. The passive type muffles extraneous sounds as the active ones electronically decrease external noise.

Passive-

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

Active-

The active noise cancellation headphones provide an additional 20dB of noise reduction than the passive type. It employs exactly the same technology (circum-aural sound dampening design) as the passive headphones but in addition incorporates phase cancellation. Here is the key feature of active noise cancelling headphones. A microphone is placed inside the headphone that picks up external noise that the aural cushions with the passive headphones cannot block out. The phase cancelling technologies are able to analyze the intensity and frequency with 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 those intents and purposes, eliminates the sound.

The headphone speaker then plays this "non-sound" in addition to whatever it is that you are listening to. This artificial noise will be the exact opposite from the extraneous noise that makes it past the ear cushions. Then they cancel each other out as a result of 180-degree phase reversal. Because of this the external noise is reduced significantly, allowing you to enjoy your audio using a dramatic reduction in background noise.

These types of headphones are perfect for airplanes or any place where there is a lot of external noise. On airplanes, for instance, this type of noise reduction while using headphones will dramatically reduce fatigue.

Another among the two would be that the active type needs a power source, normally a battery.

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