Cooler Master CM Storm Sirus 5.1 review

In the last few years we've seen a number of 5.1 headsets, which use multiple speakers in each earpiece to give you real surround sound for games and movies with 5.1 soundtracks. To go with the dedicated surround sound headset, Cooler Master's CM Storm Sirus 5.1 has an external USB sound card. It connects to your PC via two USB cables - it's a power-hungry device, hence the need for the extra connection. We were pleased to find that, unlike some audio devices which require a second USB connection for power, there was no unpleasant background hum caused by the power circuitry.

Both the headset and the audio processor are distinctly chunky. The headset reminds us of Plantronics' 777 virtual surround-sound model (see Editor's Choice), with its thick plastic headband and solid earpieces. There's plenty of padding on both, though, and we were pleased to find that - despite its weight - the headset didn't become uncomfortable during a three-hour gaming session. It fits a variety of head sizes, and although it clamps tightly to your skull with very little range of movement in the earpieces, we found it easy to wear even over glasses.

The audio processing unit is a circular, puck-shaped affair, with a volume knob, mute buttons, a pair of USB connectors emerging from one side and a female DIN plug on the other. All you have to do is connect the headset to the DIN plug and you're ready to go.

The headset's cable measures 1.3m, and you get a total 3.5m of cable if you connect the USB audio processor. If you already have a high-end sound card and wish to use its analogue surround-sound audio output, you can connect the headset to the supplied analogue adaptor, which consists of four jack plugs and a USB connector to take care of the headphones' power requirements. In general, we recommend using the headset's own USB sound card, though, particularly if all you have is your motherboard's audio.

In games, the surround effect is amazing. We compared it with virtual surround sound processing output through a decent stereo headset and were suddenly immersed in a different world of sound. The voices of the characters around us were precisely positioned, and we were keenly aware of the ominous sound of approaching monsters. This accurate directional audio gives you an obvious advantage in multiplayer games as well, as you'll be able to hear exactly where your enemies are shooting from. We were also pleased to find that, in the well-designed soundscapes of the games we tested, the music remained in the background, unaffected by any unwanted directionality.

The clarity of sound is phenomenal, particularly on human voices, while sound effects - explosive ones in particular - benefit from the headset's emphatic bass. Surround sound in films gets all the same benefits, although the headset's weight and size make it less than ideal if you want to lay back and relax. Even stereo music sounds fairly good, with a wide soundstage as well as clear bass and treble, although mid-tones sound a little muddy on our most complex and busy tracks. The noise-cancelling microphone does a good job for in-game communication, without an excess of background noise or any distortion.

The CM Storm Sirus 5.1 sounds far better than any virtual surround sound system, and it's brilliant for hardcore gamers, although stereo music performance is something of an afterthought. The headset, although heavy, is comfortable to wear for extended periods of time. However, this is a specialist product, and - at almost £100 - the price is prohibitive to casual users. If you want top-notch directional audio for gaming, this is a great buy, but most users will appreciate the lower price and greater versatility of a virtual surround-sound headset such as the Plantronics Gamecom 777 .