Many of us use headphones every day - whether its for gaming on our PCs, or on our PSPs, or whether it's just walking down the street with an iPod. How aggravating are the little intrusions?
The air conditioning in the office. The rumble of the train tracks. The constant whine of aeroplane engines. All of these disrupt our enjoyment of our music or entertainment, and a recent wave of headphones are on the market in a bid to get rid of these annoyances and allow us to enjoy our music in peace.
Active noise cancelling requires a powered circuit which produces what is effectively an inverse wave form. Tiny microphones sample outside noise and an on-board DSP calculates an inverse waveform - anti-noise - which is then emitted inside the headphones, cancelling out the unwanted background noise. It works best for continuous droning - you will still be able to hear people talking. The effect is absolutely amazing. You can be sitting in a fairly busy, air-conditioned office environment, put these on, and suddenly hear (or not) complete silence. It's eerie.
Unfortunately, the inverse wave form is not always exactly correct, and the side effect of this is that the headphones sometimes sound like they have a background 'hiss', much like the hiss from analogue tapes, accompanying the silence. The better the headphones, the less hiss, usually.
We pulled together three sets of headphones that are separated by £35 in price, top to bottom, with the cheapest at £40 and the most expensive at £75. We wanted to test how good the headphones were at reproducing sound, how effective the noise cancelling was, how comfortable they were to wear for lengthy periods and what kind of value they offered. The following pages are the result of this testing.