Noise Cancelling Headphones - The Basics of How They Block Unwanted Noise991993

There are basically 2 kinds of headphones created to reduce background noise. Passive noise cancelling headphones and noise cancelling microphone app. The passive type muffles extraneous sounds as 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 of the cup consists 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 passive type. It employs exactly the same technology (circum-aural sound dampening design) since the passive headphones but additionally incorporates phase cancellation. Here is the key feature of active noise cancelling headphones. A microphone is placed inside the headphone that accumulates external noise that the aural cushions from the passive headphones cannot block out. The phase cancelling technologies are able to analyze the intensity and frequency from the pitch, also known as the loudness and pitch from the noise. The circuitry then creates a perfect replica with 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" in addition to whatever it is that you are listening to. This artificial noise will be the exact opposite from the extraneous noise which makes it past the ear cushions. Then they cancel one another out due to the 180-degree phase reversal. Consequently the external noise is reduced significantly, allowing you to enjoy your audio with a dramatic decrease in background noise.

These kinds of headphones are fantastic for airplanes or anywhere where there is much external noise. On airplanes, for instance, this type of noise reduction while using the headphones will dramatically reduce fatigue.

Another distinction between the two is that the active type requires a power source, usually a battery.

Noise cancelling headphones are usually larger and heavier that regular headsets or earphones. They are able to, 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.