buying guide: The best noise-cancelling headphones available today

Best noise-cancelling headphonesWhen it comes to noise-cancelling headphones, there are two types to look out for: active and passive. Passive means that when the headphones are pressed against your head, some sound is cut out in the process of closing your ears off to the world outside. It's not high-tech. Lots of headphones claim that this is some sort of advanced technique, but it's nothing more than a few layers of foam trying their darndest to keep sound out.Active noise cancellation, on th