Noise Cancelling Headphones - The fundamentals of How They Block Unwanted Noise3338340

You can find basically two types of headphones designed to reduce background noise. Passive noise cancelling headphones and noise cancelling software mac. The passive type muffles extraneous sounds even though the active ones electronically decrease external noise.

Passive-

Passive noise cancelling headsets use what is called circum-aural sound dampening design. They may be shaped like a single cup, which surrounds the ear. The rim with this cup is made 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 than the passive type. It employs exactly the same technology (circum-aural sound dampening design) because the passive headphones but in addition incorporates phase cancellation. This is the key feature of active noise cancelling headphones. A microphone is put inside the headphone that picks up external noise the aural cushions of the passive headphones can't block out. The phase cancelling technology is able to analyze the intensity and frequency from the pitch, also referred to as the loudness and pitch of the noise. The circuitry then creates a perfect 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 is the exact opposite of the extraneous noise that means it is past the ear cushions. They cancel one another out due to the 180-degree phase reversal. As a result the external noise is reduced significantly, letting you enjoy your audio with a dramatic decrease in background noise.

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

Another difference between the two would be that the active type requires a power source, often a battery.

Noise cancelling headphones are usually larger and heavier that regular headsets or earphones. They can, however, become more comfortable when worn for long periods of time as a result of large cushions that impose less pressure about the ears.