Noise Cancelling Headphones - The Basics of How They Block Unwanted Noise869157

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

Passive-

Passive noise cancelling headsets use what is known as circum-aural sound dampening design. They may be shaped like a cup, which surrounds the ear. The rim with this cup consists 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 exactly the same 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 positioned inside the headphone that sees external noise how the aural cushions from the passive headphones cannot 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 with 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" in addition to whatever it is that you are listening to. This artificial noise will be the exact opposite of the extraneous noise which makes it past the ear cushions. They cancel each other out as a result of 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 perfect for airplanes or any place where there quite a bit of external noise. On airplanes, as an example, this type of noise reduction while using the headphones will dramatically reduce fatigue.

Another difference between the two would be that the active type needs a power source, usually a battery.

Noise cancelling headphones tend to be larger and heavier that regular headsets or earphones. They can, however, be more comfortable when worn for too long periods of time because of the large cushions that impose less pressure about the ears.