Noise Cancelling Headphones - The basic principles of How They Block Unwanted Noise31279

You can find basically two types of headphones developed to reduce background noise. Passive noise cancelling headphones and Noise Cancelling Software. 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 up to 20 dB of noise.

Active-

The active noise cancellation headphones provide an additional 20dB of noise reduction compared to 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 put inside the headphone that accumulates external noise the aural cushions from the passive headphones can't block out. The phase cancelling technology is able to analyze the intensity and frequency with the pitch, also referred to as the loudness and pitch of the noise. The circuitry then creates an exact replica with 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 will be listening to. This artificial noise may be the exact opposite from the extraneous noise that makes it past the ear cushions. They cancel the other person out due to the 180-degree phase reversal. Because of this the external noise is reduced significantly, enabling you to enjoy your audio having a dramatic reduction in background noise.

These kinds of headphones are perfect 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 among the two is that the active type requires 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 as a result of large cushions that impose less pressure on the ears.