What is noise-cancelling?
We all listen to music or watch videos using headphones every day. We all commute to school using trains and buses. However, unwanted noise generated by these vehicles can reduce the quality of our listening experience. So, companies, such as Bose, came up with the technology called noise cancellation. This technology enables us to listen to the sound more clearly as if we are listening in a quiet place. Some of you might have AirPods, Bose headphones, Beats headphones, etc. These headphones are famous for their noise cancellation technology. In this article, I will explain how this technology works.
The two ways of noise cancellation
There are mainly two ways of noise cancellation: active and passive. Passive noise canceling is done with the headphone itself meaning that it blocks out the sound with the material that is used. Passive noise-canceling headphones use layers of high-density foams and sound-absorbing material. Since these headphones don’t require any advanced technology, they are way cheaper than active headphones. On the other hand, active noise-canceling headphones are expensive due to their advanced built-in technology. Active noise-canceling headphones create a sound that can reduce noise from the background which makes the sound more clear.
How do active noise-cancelling headphones work?
Active noise-canceling headphones have a hidden microphone that listens to the noise on the background. The headphones process these noise waves and create the opposite waves, also known as the 180° phase shift. By doing this, the waves cancel each other which annihilates the noise in the background. This could be seen in the diagram below, the two waves cancel each other and create a square wave. This is a concept in physics called destructive interference. Since the noise cancellation works all the time and uses electronics, when it is turned on, it uses a lot of battery than the passive ones. Yet, people prefer these headphones to passive ones due to its superb sound quality.
Products/Price
Bose is known for its noise cancellation technology. They have the best noise cancelling headphones. Bose noise-canceling headphone 700 is the most famous headphone they have and it is the best in noise-canceling technology. Other companies, such as, Beats also have similar level sound quality as well. Headphones with noise canceling can be expensive ranging from $70 to $400.
[1] Harris, William. (2011). “How Noise-canceling headphones Work”. HowStuffWorks. https://electronics.howstuffworks.com/gadgets/audio-music/noise-canceling-headphone3.htm Last Accessed: 16 September 2020
[2] Carbone, Sara. (2020). “Google Pixel Buds vs Samsung Galaxy Buds Live”. SoundGuys. https://www.soundguys.com/google-pixel-buds-vs-samsung-galaxy-buds-live-39202/ Last Accessed: 16 September 2020.
[3] Philippides, Alexis. (2011). “Active noise cancelling vs. passive sound isolating headphones, a primer in noise control”. Stuff-Review. https://www.stuff-review.com/2011-11/audio-basics-a-primer-in-noise-control-active-noise-cancelling-vs-passive-sound-isolating-headphones/ Last Accessed: 16 September 2020.
[4] Thomas, Christian. “Best noise cancelling headphones”. SoundGuys. https://www.soundguys.com/best-noise-cancelling-headphones-5220/#:~:text=Bose%20has%20made%20a%20name,than%20the%20Bose%20QC35%20II. Last Accessed: 16 September 2020.
[5] Bazoyan, Anna. “What’s the Future of Noise Cancelling Headphones?”. Krisp.https://krisp.ai/blog/noise-cancelling-headphones-future/ Last Accessed: 16 September 2020.
[6] “BEATS Studio 3 Wireless Bluetooth Noise-Cancelling Headphones – Shadow Grey”. Currys PC World. https://www.currys.ie/ieen/audio-and-headphones/headphones/headphones/beats-studio-3-wireless-bluetooth-noise-cancelling-headphones-shadow-grey-10170338-pdt.html Last Accessed: 16 September 2020.
[7] CNET. (2015). “How do noise-cancelling headphones work?”. https://www.youtube.com/watch?v=F7D_pnaexG0&ab_channel=CNET Last Accessed: 16 September 2020.
Thumbnail Images:
https://www.beatsbydre.com/ (Beats headphones) Last Accessed: 16 September 2020.
https://www.apple.com/ (AirPods Pro) Last Accessed: 16 September 2020.
https://www.bose.com/en_us/index.html (Bose headphones) Last Accessed: 16 September 2020.
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