What Is Passive and Active Noise Cancellation?

The choice between passive and active noise cancellation depends on your preferences and lifestyle. Passive noise cancellation offers an effective solution without relying on batteries, ideal for those who value simplicity and do not want to sacrifice sound quality. Discover the details of passive noise cancellation and learn the difference with active noise cancellation, so you can choose the right one.  

Noise cancelling headphones are a technology designed to minimise or eliminate unwanted sounds from the environment. Below we’ll dive a little deeper into the key features that make noise cancelling headphones special:

Sound insulation pads

They are made from special materials, such as memory foam or high-quality synthetic leather. They are designed to seal your ears comfortably and effectively. This creates a physical barrier that helps block out ambient noise.

Over-ear or in-ear design

Noise-cancelling headphones come in two main styles. Over-ear headphones, which completely cover your ears , offer more complete isolation and are ideal for cancelling out persistent background noise. In-ear headphones, on the other hand, are inserted into the ear canal and feature ear cushions that also offer isolation, albeit in a lighter form.

Sound pickup microphones

They can be located either on the outside or inside of the headphones. External microphones pick up ambient sound, while internal microphones monitor the sound inside your ears . This information is crucial for active cancellation, as the system needs to know which noise to remove.

Good quality sound processor

The processor analyzes the sounds picked up by the microphones and generates reverse sound waves to neutralize them. 

Configurable noise cancellation system

Some headphones allow you to adjust the level of noise cancellation to your preference . This is useful if you’re in environments where you want to hear some ambient sound, such as when you’re out and about and need to stay alert.

Long duration battery

Since active noise cancellation requires power, it is essential that the headphones have a high-capacity battery. This ensures that you can enjoy your music without interruptions for hours .

Impeccable audio quality

While noise cancellation is crucial, we must not forget about sound quality. Good noise-cancelling headphones also offer a good listening experience, with deep bass and clear treble .

What is Active Noise Cancellation (ANC)?

Active noise cancellation, or ANC, is a technology used to reduce or even eliminate unwanted noises around you while you’re enjoying your favorite music or content through your headphones.

How does active noise cancellation work?

  • Signal processing: Once the microphones detect ambient noise, they send that information to a small but powerful processor inside the headphones.
  • Reverse Wave Generation: This processor goes to work and generates sound waves that are identical but in opposite phase to the noises it is detecting. This means that if there is a low frequency sound coming from outside, such as the noise of an engine, the headphones will produce a sound wave that cancels out exactly that frequency.
  • Noise cancellation: When these inverse waves combine with the original noise, a sort of “collision” occurs between the waves, causing them to cancel each other out. The result is that you virtually never hear that annoying sound.

What is passive noise cancellation?

Passive noise cancellation, unlike active noise cancellation, does not involve sophisticated processors or electronic components. Instead, it relies on physical design and special materials to block or reduce outside noise.

How does passive noise cancellation work?

  • Isolating ear cushions: One of the most important features of passive noise-cancelling headphones is the ear cushions. These are made from special materials that are designed to provide a tight seal around your ears . This means they fit comfortably and create an effective barrier against noise.
  • Good design: In addition to the ear cushions, the very structure of the headphones is designed to minimize the entry of external noise . This can include elements such as a closed or semi-closed design that prevents sound from entering.
  • Sound Isolation: The materials used in the manufacture of passive noise cancelling headphones are selected to absorb and disperse noise . This means that instead of trying to cancel out noise like active ANC, these materials absorb it and convert it into heat.

For long plane trips, active noise cancellation can be your best ally. However, if you prefer an option without the need for charging and with good audio quality, headphones with passive noise cancellation may be your best choice.