Noise Cancelling Headphones - The fundamentals of How They Block Unwanted Noise7430368

You will find basically two types of headphones designed to reduce background noise. Passive noise cancelling headphones and background noise reduction. 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 are shaped like a cup, which surrounds the ear. The rim with this 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 produce an additional 20dB of noise reduction than the passive type. It employs the identical technology (circum-aural sound dampening design) as the passive headphones but also incorporates phase cancellation. This is actually the key feature of active noise cancelling headphones. A microphone is positioned inside the headphone that sees external noise that the aural cushions with the passive headphones cannot block out. The phase cancelling technologies are able to analyze the intensity and frequency from the pitch, also called the loudness and pitch with the noise. The circuitry then creates an exact replica from 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're listening to. This artificial noise will be the exact opposite of the extraneous noise that means it is past the ear cushions. They cancel the other person out as a result of 180-degree phase reversal. As a result the external noise is reduced significantly, allowing you to enjoy your audio with a dramatic decline in background noise.

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

Another among the two is the active type needs a power source, often a battery.

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