Active Noise Cancellation (ANC) is the latest buzzword when it comes to the world of headphones. It is one of those things most people ask about when they are purchasing a pair of headphones – “do they have ANC?” or if you happen to be really geeky “how many levels of ANC do they have?”
ANC is basically a way in which the headphones keep external sound out. Basically, ANC headphones have special microphones that listen to external sound (the sound of traffic, chatter in a cafe, the hum of an aircraft’s engine, and so on) and then generate their own sound waves to cancel out these sounds. In essence, with a good pair of ANC headphones, you can focus only on what you are listening, with outside sound being blocked out. It is a highly talked about feature, hyped up by brands and covered in detail by reviewers.
The funny part? You might not actually even need ANC.
Before you get shocked by that statement, just consider the following:
It does not always shut out ALL the sound
For all the hype around ANC, the fact is that it does not always shut out all the sound around you. A lot depends on the kind of sound that is in your vicinity. Sitting in a cafe, ANC might drown out the chit chat and the music playing in the cafe. However, if the cafe is a very noisy one and there are sudden sounds like the crashing of cups, or the dropping of vessels or the running of grinding machines, well, ANC cannot kill all that. It will drown the sound of your car’s motor, or maybe the Metro’s engine, but the sound of two people talking loudly near you in all probability cannot be handled. You are very rarely going to get absolutely zero sound from outside.
Only the really expensive ANC headphones really work
Just because a pair of headphones comes with an ANC label does not mean it has high quality ANC. As it involves a fair bit of tech (microphones, processing software and so on), ANC is an expensive technology. Of course you get less expensive versions of it too. The problem is that they do not work that well. In fact, even some expensive headphones do not have good ANC – you generally have to go beyond Rs 15,000 (USD 200 and above) to get headphones with effective ANC.
It does not affect sound quality (no, really it does not)
For all the hype around ANC, the fact is that it does not actually affect the quality of sound that your headphones produce. So, your headphones will not give you great quality audio just because they have ANC. What they will do is keep external sound out. ANC has ZERO impact on the sound quality of headphones. It is about sound outside the headphones, not in the headphones. It is perfectly possible to have headphones with great ANC and lousy sound (we know a few).
It is of no use without good padding or a snug fit
You know, you could have all the fancy ANC in the world and it would be useless if the headphones did not have enough padding or did not fit snugly into or around your ears. At the end of the day, the fit of the headphones is what provides the first layer of protection against external noise (called passive noise cancellation or noise isolation). ANC is effective only if the headphones themselves are designed to keep out external sound.
It can sometimes work too well for your own comfort
There is the other side to ANC – if it works too well, you might actually miss hearing sounds that you need to hear. We have seen instances of people being struck by vehicles because they did not hear them coming, thanks to their ANC headphones. No, they do not TOTALLY drown out traffic sound but they make it fainter, so you might not actually realise how close a car or a bike behind you is! You might also out your name being called unless it is from really close and really loud. Or if you are at home, you might miss someone calling you for tea or lunch, and if the ANC is really working, even the ringing of a phone if it is in a different room!
One more thing: ANC chews up battery life
If you want headphones with a lot of battery life, you might want to consider giving the ANC ones a miss. ANC can really eat up your headphone’s battery – sometimes even halving its battery life. In the case of wired headphones, you even need to charge the ANC component separately.
So there you go: it works only in expensive variants, affects battery life and most importantly, has no effect on audio quality. We are not saying it is useless – it is great for those who need to focus on work and block out a lot of external sound. But it is not really needed for everybody. Unless you are really looking for a LOT of silence – and have the bucks to finance it – we would actually suggest you prioritise sound quality and fit above ANC in most headphones.