Noise Cancelling Headphones - The Basics of How They Block Unwanted Noise5020329

You can find basically two types of headphones developed to reduce background noise. Passive noise cancelling headphones and app for noise cancelling. 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 of the cup is constructed of a high-density foam and sound wave dampening material. This results in a seal that blocks approximately 20 dB of noise.

Active-

The active noise cancellation headphones provide an additional 20dB of noise reduction compared to passive type. It employs the identical technology (circum-aural sound dampening design) as the passive headphones but also 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 the aural cushions from the passive headphones are unable to block out. The phase cancelling technology is able to analyze the intensity and frequency of the pitch, also known as the loudness and pitch from the noise. The circuitry then creates a precise replica from the noise and throws it 180 degrees out-of-phase. This, for many intents and purposes, eliminates the sound.

The headphone speaker then plays this "non-sound" together with whatever it is that you're listening to. This artificial noise may be the exact opposite with the extraneous noise that makes it past the ear cushions. They then cancel one another out because of the 180-degree phase reversal. Consequently the external noise is reduced significantly, letting you enjoy your audio having a dramatic decline in background noise.

These types of headphones are fantastic for airplanes or any place where there quite a bit 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 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 very long periods of time because of the large cushions that impose less pressure on the ears.