Headphones For Blocking External Noise

It’s really annoying when you’re trying to listen to music and there’s too much noise in the background. The real problem is that the whole reason we have things like mp3 players and headphones is because we want to take our music wherever we want, and outdoors is where all the noise is! Cars, buses, trains, crowds, they’re all a lot less enjoyable than what you want to listen to! Yet that’s what you’ll have to hear, unless you put the volume up so loud you destroy your eardrums! (You might like your music that loud, but still.)

So if we can’t avoid the noise, how do you get rid of it? It’s quite interesting how this problem has been solved by some headphones manufacturers. The two main methods are noise isolation and noise cancelling.

Noise isolation is quite simple. It basically means that the headphones are worn in such a way that they seal off the ears or the ear canal from the noise, effectively muffling it. It’s often used for earbud headphones, because they have to sit firmly in the ears anyway, which means the cushioning over the speakers serves two purposes, providing hold as well as noise isolation. Often, though this isn’t as effective as you’d like, but it’s generally effective enough for cheaper earphones.

Noise cancelling on the other hand, is quite a clever, almost ingenious method. This involves a bit of knowledge about how sound works, but it should be easy to explain: Sound is basically a wave pattern in the air. What you’d hear normally, when listening to music, would be the music wave, plus the external noise wave. Noise cancelling headphones use a little microphone on the outside of the headphones to pick up and invert the noise wave into its negative, then adds that to the music. So you’ve got the music, minus the noise, plus the noise. The minus and plus of the noise wave will cancel each other out, leaving you with just the music!

It’s a long way from absolute selective hearing, but it works well for now. And you’ll notice how much more enjoyable music is without a baby crying in the background!