How Do Noise-Canceling Headphones Work?

How Do Noise-Canceling Headphones Work

Noise-canceling headphones are often misunderstood. That is not to say they are not great products but it is critical that you understand what you are getting when you invest in audio equipment. We will look at what these headphones can and can’t do and answer the question – how do noise-canceling headphones work?

Noise-calling headphones employ a technology called ANC or active noise-cancellation. Microphones are used to absorb low-frequency ambient sounds. The technology then neutralizes these sounds so they are not heard by the user. They might not be able to eliminate all ambient noise but they can certainly reduce it. 

The headset itself generates its own sound. This sound is phase-inverted and works against the incoming sound thereby canceling it out. This process is also known as anti-phase. Quality noise-canceling headphones can reduce external noise by as much as 30dB, sometimes even higher. 

To understand this better it is is easier to think of the way sound travels which is in waves. The height (amplitude) and shape (wavelength) of the outgoing sound used in noise-canceling are designed to counteract or balance out the incoming waves, effectively blocking the sound and canceling it out.  

It gets a bit more technical than that but that s the basic principle. 

The results are more effective on continuous low-frequency noise such as the drone of an airplane engine or traffic noise. They are not that effective against higher frequency or short sounds. Noises such as breaking glass or voices are not blocked effectively. 

How did noise-canceling headphones develop? 

They were initially created in the 1950s for airline pilots. The idea was to increase their concentration and comfort on long flights without blocking important sounds. The results were effective and consumer versions were soon developed. 

Do noise-canceling headphones help?

If you invest in quality equipment then yes, this feature will certainly help. It is great for those who wish to list to music, podcasts, or other audio in a noisy environment. If you are a commuter, a student, or want to enjoy your audio in a noisy environment they are a massive benefit. 

The technology will allow you to appreciate the quality and clarity of what you are listening to with minimal outside disturbance. 

Active vs passive noise canceling

Active noise-calling should not be confused with passive noise-canceling headphones. The design and materials used in noise-canceling headphones will naturally block out some of the ambient noise. 

Some are specifically designed to enhance this effect through the use of high-density thick foam covers or other material that is known to absorb sound. While this is helpful it is more a design and construction feature and not a technology feature such as one finds in ANC or active noise-cancellation.

They generally reduce external or ambient noise by around 15 to 20 dB.

While passive noise-canceling can be useful, the downside is that it makes the headphones a lot heavier and bulkier. It can make for very comfortable headphones, however, in the right environment. 

Final thoughts

Quality active noise-canceling headphones are a great benefit when you want to appreciate quality audio in a noisy environment. They are a worthwhile feature to consider when deciding on the best headphones for your needs. 

This article was last updated on April 8, 2021 .

By Charl Jooste

Writing full time from home, Charl enjoys modern technology and advanced gadgets but still has a soft spot for quality reliable appliances. He is passionate about durability and quality going to great lengths to find the very best ideas and leading products to share with readers.