Noise Cancelling Headphones - The fundamentals of How They Block Unwanted Noise2395471

There are basically two kinds of headphones developed to reduce background noise. Passive noise cancelling headphones and remove background noise from video app. The passive type muffles extraneous sounds while the active ones electronically decrease external noise.

Passive-

Passive noise cancelling headsets use what is known circum-aural sound dampening design. They are 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 creates a seal that blocks approximately 20 dB of noise.

Active-

The active noise cancellation headphones provide an additional 20dB of noise reduction compared to the passive type. It employs the same technology (circum-aural sound dampening design) since 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 accumulates external noise the aural cushions with the passive headphones can't block out. The phase cancelling technology is able to analyze the intensity and frequency from the pitch, also called the loudness and pitch from the noise. The circuitry then creates a precise 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" together with whatever it is that you are listening to. This artificial noise may be the exact opposite of the extraneous noise that means it is past the ear cushions. They then cancel the other person out as a result of 180-degree phase reversal. Consequently the external noise is reduced significantly, letting you enjoy your audio with a dramatic decline in background noise.

These kind of headphones are perfect for airplanes or anyplace where there is a lot of external noise. On airplanes, for example, this type of noise reduction with all the headphones will dramatically reduce fatigue.

Another difference between the two is the active type requires a power source, often a battery.

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