Hello Mi Fans,
As you already know, Mi India recently launched their latest flagship phone Mi Mix 2 and along with it, a really cool new accessory was launched, Mi Noise Cancelling Earphones. Today I will tell you everything that you need to know about Active Noise Cancellation/Control (ANC), how it works and does it really work. Let’s get started.
What Is Noise Cancelation?
Noise Cancelation is technique used in modern headphones to remove external noise so that the listener can hear quality sound and no interference and the sound doesn’t leak out. Technically, all headphones and earphones use some form of ‘noise isolation’ or passive noise cancellation.
In addition to noise isolation, ANC headphones have an inline mic which is used to block out noise. Due to this mic, these headphones consume more power than regular ones and this is why our Mi Noise Cancelling Earphones uses USB type C connection with which it gets more juice to power the circuit.
Passive vs Active Noise Cancellation
Passive Noise Isolation
As I wrote earlier, Noise isolating earphones and headphones block out ambient noise without any extra power. Adjustable-fit eartips on earphones and extra earcup padding on headphones act as physical barriers to keep unwanted noise from reaching your ears. These barriers also help prevent people around you from hearing your music. Noise isolation is not very efficient at blocking noise as it all depends on how good the it seals your ear which in turn depends on your ear size and shape. The experience will vary from person to person.
Active Noise Cancelation
For additional noise cancelation beyond passive noise isolation, internal and external microphones in the headphone measure unwanted ambient noises, then circuitry in the headphones generate sound at a frequency that cancels out those noises. Active noise cancelation works whenever headphones with this feature are turned and otherwise noise isolation still works. It is very efficient at cancelling out noise and it works regardless your ear shape and size but will benefit good seal by providing more isolation. (source)
How Does Active Noise Cancellation Work?
According to Wikipedia, Sound is a pressure wave, which consists of alternating periods of compression and rarefaction. A noise-cancellation speaker emits a sound wave with the same amplitude but with inverted phase to the original sound. The waves combine to form a new wave, in a process called interference, and effectively cancel each other out – an effect which is called destructive interference.
Adaptive algorithms are designed to analyze the waveform of the background aural or nonaural noise, then based on the specific algorithm generate a signal that will either phase shift or invert the polarity of the original signal. This inverted signal is then amplified and a transducer creates a sound wave directly proportional to the amplitude of the original waveform, creating destructive interference. This effectively reduces the volume of the perceivable noise.
In layman’s terms, the inline microphone picks up the external noises which is then processed by the circuit and a soundwave which is opposite to the noise is developed. This anti-noise is then sent to the headphone speaker along with the music that you’re listening to. The anti-noise then cancels out the noise effectively making your experience free from external sounds. This all happens in real time and so the noise is cancelled out instantly with no lag.
Do You Need Noise Cancelling Headphones?
Before even thinking of buying a ANC headphone, check if your device is compatible with it, even our Mi Noise Cancelling Earphones currently only work with Mi Mix 2 and Mi5. Many other headphones require batteries which in turn makes them bulky and you need to charge or replace those batteries.
If you travel a lot by air or go to crowded places a lot then ANC headphones are a must buy but even if you’re not then you should still consider trying it out once as these headphones pack amazing drivers that already provide great sound quality. Oh, and one last thing, ANC headphones do cost quite a bit more than regular headphones.
So, do you use Active Noise Cancellation headphones or not? Also,let me know in comments, what do you think about ANC technology.