Noise Cancelling Headphones - The Basics of How They Block Unwanted Noise5874235

There are basically two kinds of headphones developed to reduce background noise. Passive noise cancelling headphones and digital noise cancelling technology. The passive type muffles extraneous sounds as 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 this cup consists of a high-density foam and sound wave dampening material. This produces a seal that blocks as much as 20 dB of noise.

Active-

The active noise cancellation headphones provide an additional 20dB of noise reduction compared to passive type. It employs the same technology (circum-aural sound dampening design) since the passive headphones but also incorporates phase cancellation. This is actually the key feature of active noise cancelling headphones. A microphone is placed inside the headphone that sees external noise how the aural cushions of the passive headphones are unable to block out. The phase cancelling technologies are able to analyze the intensity and frequency of the pitch, also called the loudness and pitch with the noise. The circuitry then creates a perfect replica from 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 may be the exact opposite with the extraneous noise that means it is past the ear cushions. They then cancel one another out as a result of 180-degree phase reversal. Because of this the external noise is reduced significantly, allowing you to enjoy your audio having a dramatic decrease in background noise.

These types of headphones are fantastic for airplanes or anywhere 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 is that the active type takes a power source, usually a battery.

Noise cancelling headphones are generally larger and heavier that regular headsets or earphones. They can, however, become more comfortable when worn for very long periods of time because of the large cushions that impose less pressure around the ears.