5.1 surround sound is a multichannel audio technology that uses the six-channel surround technique. This technique uses five full-bandwidth channels that operate at a frequency of 3-20,000 hertz, targeting the front left, right, center and right and left surround, as well as one subwoofer channel that operates at a frequency of 3-120 Hertz for low-frequency effects.
5.1 surround-sound technology is considered the minimum required for speakers that provide true surround-sound effects. It is considered an industry standard and is supported by all DVDs, video games, and many other types of media.
Techopedia explains 5.1 Surround Sound
5.1 surround sound's cost can vary based on the channels and configurations, but is still considered cheaper than other technologies in providing the best sound effect possible. Because 5.1 surround sound has more audio speakers for output and sound recording has more audio channels, it provides more realistic sound and more depth to users' listening experience. For a centered-positioned audience, 5.1 surround sound helps in proper localization and brings in equability from all audio sources. It is also considered the backbone of the lossy sound formats and was the key component in the home theater movement. Examples of 5.1 surround sound systems include DTS, Dolby Digital, etc.
Currently, 5.1 surround sound is the preferred layout in home theaters and commercial movie theaters. It is much suited to small- and medium-sized rooms for engaging and realistic true surround-sound effects. For music and digital broadcasting, 5.1 surround sound is considered the standard audio technique.