How Does Bose Noise Cancelling Work?

by Emma Baker, Senior Editor | Published February 15th, 2024 | Reviewed by Ted Wilson, Systems Engineer

Noise cancellation is achieved through a process known as phase inversion, where the headphones produce a sound wave that is the exact opposite of the incoming noise wave.

This innovative approach effectively cancels out intrusive noises, such as traffic hum or background chatter, enhancing the listener’s experience. The technology goes beyond merely silencing unwanted noise; it’s about crafting an acoustic environment where the desired sound is delivered with utmost clarity and minimal disturbance.

headphones with sound wave

Understanding Sound and Noise

Sound waves are vibrations that travel through various mediums, including air, water, and solids. These waves have specific characteristics, such as frequency and amplitude. It’s the interaction of these waves with our auditory system that enables us to perceive different sounds. 

In everyday life, not all sounds are welcome. This is where the concept of ‘noise’ in audio terminology comes into play. Noise refers to those unwanted sounds that invade our auditory space, such as the background noise in a cafĂ© or the whir of machinery. Bose’s noise-cancelling technology is designed to identify and diminish these invasive sounds, thereby enhancing the overall listening experience.

What is Frequency?

Frequency is all about how fast the wave wiggles. Imagine a wave moving up and down quickly – that’s a high frequency, and it makes a high-pitched sound, like a bird chirping. A slower wiggle means a lower pitch, like a deep drum beat.

What is Amplitude?

Amplitude is about how big a sound wave is. A big, tall wave makes a loud sound, while a small, short wave is a quiet sound.

Basics of Noise Cancellation

Noise cancellation technology, particularly Active Noise Cancellation (ANC), is at the heart of Bose’s headphones. This technology operates on the principle of sound wave interference. Essentially, it involves the creation of a new sound wave that is the exact opposite, or “180 degrees out of phase,” with the unwanted ambient noise. When these two sound waves – the noise and the anti-noise – collide, they cancel each other out through a phenomenon known as destructive interference. This process significantly reduces the volume of the ambient noise, allowing the listener to focus on the intended audio without the distraction of background sounds.

Bose Noise Technology

Bose’s approach to noise cancellation sets them apart in the audio technology industry. Here’s a more detailed look at how Bose headphones utilize advanced features for noise cancellation:

Advanced Microphone System

  • Multiple Microphones: Bose headphones, such as the Bose 700 series, typically feature an array of strategically placed microphones. Some models use up to eight microphones, with some dedicated to voice pickup for calls and others specifically for noise cancellation.
  • External and Internal Noise Detection: These microphones are positioned both externally and internally within the ear cups. The external microphones detect ambient sounds, while the internal ones listen to the sound within the ear cup, allowing the system to adjust the noise cancellation performance in real-time.

Distinctive Features of Bose ANC

  • Level of Noise Cancellation: Bose headphones often provide different levels of active noise cancellation. For instance, the Bose QuietComfort Earbuds offer 11 levels of noise control, allowing users to tailor the amount of external sound they want to block or let in.
  • Noise Masking vs. Noise Cancelling: Bose also explores the concept of noise masking in some of its products, like the Bose Sleepbuds. This is different from noise cancellation as it involves playing soothing sounds to mask unwanted external noise, rather than canceling it out.

Effectiveness in Different Environments

A study in the journal Applied Acoustics looked into how Active Noise Cancellation (ANC) headphones, like Bose, work in different real-life situations. This research is useful for understanding how these headphones perform in various places, from quiet rooms to noisy streets.

The study shows that the basic noise blocking ability of these headphones, including Bose models, stays pretty much the same no matter where you are. This is a key point because Bose headphones use two methods to reduce noise. The first method, known as passive noise cancellation, relies on the design and materials of the headphones to block out sound. This method is effective in a variety of environments.

However, the study also discovered that the active noise cancellation part of the headphones, which actively works to cancel out background noise, can vary in effectiveness. This depends on where you are, the brand of headphones, and the technology they use. For instance, Bose headphones are great at reducing constant noises like the hum of an airplane engine. But in places with lots of changing noises, like busy city streets or construction sites, they might not be as effective.

Is Noise Cancellation Safe to Use?

Yes, ANC products are safe to use.

One of the main concerns with using headphones, in general, is the risk of hearing damage due to high volume levels. Noise-cancelling headphones can actually be beneficial in this regard. By reducing background noise, they allow you to listen to audio at lower volumes, which can be safer for your ears. However, it’s important to keep the volume at a reasonable level, even with noise cancellation activated.

Bose’s noise-cancelling headphones stand out due to their advanced microphone system, custom-developed algorithms for noise cancellation, and unique features that offer a high degree of personalization and adaptability. These technical aspects contribute to a superior user experience, making Bose a leader in the field of noise-cancelling audio technology.