Dispose of Active noise cancellation to block out ambient noise It is one of the features that is currently most in demand when choosing one of the best headphones on the market. In this article you will better understand what this functionality is and how it works.
How active noise cancellation works
Active noise cancellation or CAR is also known as Active Noise Control or ANC for its acronym in English. It is a functionality that many headphones or helmets include to minimize environmental noise as much as possible. To achieve this they are based on the wave interference theory.
The principle of wave interference says that when two or more waves impinge on a point, a total wave is created which is the vector sum of all the incident waves. Starting from this basis, an artificial sound wave – destructive interference – can theoretically be created that is responsible for providing a wave opposite to the signal we perceive and whose sum results in zero.
Taking this into account, The opposite wave created by the headphones is not completely null, but it does manage to significantly attenuate external noise. Based then on the principle of interference, the original signal would be the music or audio that we want to hear plus the surrounding noise. The wave created by the headphone circuits would be the artificial signal.
For headphones to capture external noise, they use the built-in microphones, which is vital to recognize which noise they should “make disappear.” Furthermore, if good pads are added to quality microphones, the result is much more optimal.
On the other hand, headphones with this type of cancellation usually work better in low frequency and constant noises such as that produced by car or airplane engines, fans, or computer equipment, among others.
Difference between active and passive noise cancellation
Noise cancellation serves, broadly speaking, to block the sound we don’t want. And to do this, there are two ways to do it, through passive noise cancellation and through active noise cancellation.
The Passive cancellation is the cheapest and most common. It is carried out through acoustic insulation systems so that outside sound does not enter the auditory system. For this, an insulator is usually included between the casing and the part that goes near the ear.
The big difference with active cancellation is that passive attenuates noise more than cancels it. What it does is minimize ambient sound noise through the headphones’ own design.
