The number of speakers you need is determined by the quality of sound you want to achieve. In general, five speakers should be sufficient for most purposes. Most people prefer to have two center channels and one pair of side speakers, as well as a surround speaker for ambiance or to create a wider stereo image. It’s also possible to use just a single center channel and a subwoofer. Regardless, what matters most is that you get quality sound where you need it.