What is Noise Cancellation and how does it work?

Noise Cancellation is a term we see in almost all headphone advertisements and packaging nowadays. But there are different kinds of noise cancellation and the method to cancel the noise are also different. Today you will understand the types of noise cancellation and the various methods used to do that cancellation.

Types of Noise Cancellation

There are two broad types of Noise Cancellation: Noise Cancellation in Microphones, Noise Cancellation in Headphones

Noise Cancelling in Microphones

This doesn’t help the speaker directly. Instead, Microphone Noise Cancellation helps the person who is on the other side of the line, this kind of cancellation makes the voice of the speaker clearer by suppressing the noises and the sounds of the surroundings of the speaker.

Different ways are used to achieve noise cancellation in microphones.

Microphone manufacturers often make changes in size, shape, and digital processing of the sound to make the voice clearer.

Another way to do noise cancellation in microphones is by the help of a multi-mic setup. If you look closely your phone may have two mics. How this setup works is that mic is placed in such a way that it is close to your mouth while the other one is placed in such a way that it picks up all the sounds of the surrounding. With the use of some digital algorithms, they subtract the sounds of the surrounding making it easier for the other end to listen to you.

Noise Cancelling Headphones

Noise cancellation in headphones directly affects you. Instead of blocking noises for the other person, it blocks noises for you while you are wearing these headphones. It helps you focus on the thing you are listening to or the work you are doing by blocking sounds from around you.

There are broadly two kinds of noise cancellation that work in headphones, Passive Noise Cancellation and Active Noise Cancellation.

• Passive Noise Cancellation- Noise cancellation achieved by physical features of headsets is called Passive Noise Cancellation. This type of noise cancellation completely depends on the shape and the material of the headphones. So there is no special technology being used in this, manufacturers try to deceive customers by using these fancy terms. However, this works very effectively for irregular or high-frequency sounds.
• Active Noise Cancellation- Very popularly known as ANC (Active Noise Cancellation), this method actively cancels the noise with the help of microphones. ANC headphones pick up the noise of the surroundings and create anti-noise which eventually cancels various kinds of sounds that repeat themselves regularly. Sounds of a ceiling fan, someone humming a song, sound coming from tv e.t.c. can be effectively minimized.

Final words

In recent two-three years, various big brands including Apple have done fabulous work with ANC technology. They have made very good headphones that you can try and you will feel the magic of ANC.

But beware of deceptive marketing, do not buy headphones with passive noise cancellation by confusing them with ANC.