These in-ear, noise-isolating headphones feel be a little strange when you first start using them - but don't let that put you off.

Sony and Sennheiser have been offering this headphone technology for a few years now. It has stood the test of time, and is probably here to stay for a few more years whether you like it or not!

The concept behind the CX 400s is simple; block out all the ambient noise with snug fitting rubber in-ear phones and let the sounds from your MP3 player spurt directly into your ear, unhindered by spillage from the outside world. And it works. So well in fact, that you cannot hear nearby cars, or people trying to talk to you in the street.

Bass tones are delivered full and punchy, while trebles are pristine and glossy. Headphone technology has progressed an awful lot on the last decade, and products such as the CX 400 are testament to the extensive research and development carried out by those at the forefront of audio reproduction, and Sennheiser can proudly claim to be in that elite group!