What does surround sound mean?

The basics
The standard sound we are used to from record players, portable music players and television is in stereo, which means there are two channels. Early recordings were in mono, which means there is only one channel. Anyone listening to a mono recording will hear a single sound at any one time, whereas a stereo listener will hear two.

The two sounds are generally supplied by two speakers placed in suitable places in a room so that sound is directed separately to each of the listener’s ears. Using a surround-sound system, more speakers are placed in the room so the audio appears to surround the listener, rather than just coming from the sides.

Most home systems use 5.1. This comprises five speakers and a sub-woofer that provides deep bass sounds, represented by the ‘.1’ in the name.

Sets of 7.1 speakers are also common, and it’s even possible to get 9.1 sets, but 5.1 is by far the most widespread, best supported and easiest to set up and use. Two of the speakers go in front of the listener (left and right), two go behind (left and right again) and a centre speaker sits by the television.

The centre speaker carries most of the dialogue, along with the front speakers that also carry some music and effects, while the rear speakers are mostly used for effects.

How to get it
Home surround sound is now quite cheap to buy – home entertainment packages that combine a DVD or Blu-ray player with an amplifier and a set of speakers can cost only £100, but a decent set will cost more.

But it’s possible to get surround sound for even less than that. If you have a recent PC (bought in the last five years) it’s likely it can output surround sound, as long as you plug it into a suitable amplifier or speakers.

There are several ways to get the surround sound out of your computer and into the speakers. You will need either a set of powered speakers, which have an amplifier built in, or a separate surround sound amplifier, into which you can plug your own speakers.

In the first case, you will usually need to connect the computer to the speakers using three pairs of stereo cables.

Look for the identical 3.5mm headphone sockets on the back of the PC. They will usually be differently coloured, but you should check the manual or the manufacturer’s website to find out which colour corresponds to which speaker inputs.