Speakers' Corner: Surround sound explained

Multi-channel surround sound in the home is almost taken for granted nowadays, whether it's for watching DVDs, playing PC games or listening to surround-sound audio formats such as DVD-Audio or Sony's Super Audio CD (SACD).

Yet setting up your system for multi-channel playback isn't always simple; there's a minefield of names and acronyms to battle through, and plenty of conflicting advice on how best to enjoy surround sound.

In this feature, we go back to basics with a fascinating look at the history of multi-channel sound, then we guide you through the different formats and setting up surround sound on your Windows PC.

A brief history of sound reproduction
People realised a long time ago that, although using a single loudspeaker to reproduce sound was practical and simple, it wasn't realistic. It just didn't give the listener the feeling of 'being there'.

Ever since the first electronic recording and playback systems were invented, the quest for absolute realism in reproduced sound has been pursued relentlessly.

The principle of the moving coil loudspeaker was patented in 1924 by two Americans - Rice and Kellogg - although there is some evidence of an earlier application by the British engineer Paul Voigt.

Amazingly, in 80 years little has changed and we still use similar moving coil loudspeakers. The biggest change has been the adoption of 'stereo' reproduction through two loudspeakers to produce some illusion of direction and depth in the reproduced sound field.

The first commercially available stereo recordings were issued by RCA in 1957, first on two-track magnetic tape and then on vinyl disc. Most record companies stopped issuing mono recordings in the 1960s.

Although stereo is definitely better than mono, it still isn't entirely convincing, not least because it doesn't provide a stable sound image independent of the position of the listener.