Noise Cancelling Headphones - The fundamentals of How They Block Unwanted Noise872911

You can find basically two types of headphones designed to reduce background noise. Passive noise cancelling headphones and digital noise cancelling technology. The passive type muffles extraneous sounds even though 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 of the cup consists of a high-density foam and sound wave dampening material. This produces 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) since the passive headphones but additionally incorporates phase cancellation. This is actually the key feature of active noise cancelling headphones. A microphone is placed inside the headphone that accumulates external noise that the aural cushions of the passive headphones are unable to block out. The phase cancelling technologies are able to analyze the intensity and frequency from the pitch, also known as the loudness and pitch of the noise. The circuitry then creates an exact replica of 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 is the exact opposite from the extraneous noise which makes it past the ear cushions. They cancel one another out because of the 180-degree phase reversal. Consequently the external noise is reduced significantly, letting you enjoy your audio using a dramatic decrease in background noise.

These kind of headphones are ideal for airplanes or any place where there is a lot of external noise. On airplanes, as an example, this type of noise reduction while using headphones will dramatically reduce fatigue.

Another difference between the two is the active type takes a power source, usually a battery.

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