The principle of noise cancellation, What is noise cancellation

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What is noise cancelling?

There's a function that's always in the earphones that are released these days. It's noise cancelling. Noise cancellation is Noise Cancellation, which literally refers to the function of removing noise in English. It is a function that allows you to hear what you want through earphones without being disturbed by loud external sounds even in public transportation such as buses and subways. Noise cancellation reduces external noise so that you can enjoy movies or music you enjoy even in noisy places outside, so this feature affects many consumers in choosing earphones.

 

 

Principles of Noise Cancellation

Active Noise Cancellation
It is the principle of noise cancellation using sound offset interference. Engineeringly, sound belongs to waves. Sound with a constant wave has the characteristic that when it encounters the opposite wave, it cancels out. In other words, it's gone. Active noise cancellation uses this principle. Identify the waves (phase and amplitude) of the surrounding sound and generate the opposite waves to eliminate the noise. A typical example of using active noise cancellation is AirPods, which are often seen around our lives, have this function.

Passive Noise Cancellation
Passive noise cancellation is a way to physically remove sound. Passive noise cancellation is to remove sound using sound insulation and sound absorption materials. Typical passive noise cancellations include wearing earplugs.