Extracts Five audio channels from either a specially encoded two-channel or a stereo source:
Two channels for speakers at the front—left (L) and right (R).
One channel for speaker at the center—center (C).
Two channels for surround speakers at the rear—surround left (LS) and surround right (RS).
One low-frequency effects channel (LFE).
Describes the Dolby Pro Logic II matrixed surround system. Source media is often gaming systems including Playstation 2, GameCube and Wii games branded with "Pro Logic II" logo.
5.1 surround sound may also be referred to as 3-2 stereo. This defines the configuration that has been standardised for numerous surround sound applications. The term 3-2 refers to 3 front speakers and 2 rear speakers.
Placement: 5.1 speaker layouts should conform to the ITU-R BS.775 standard, despite the myth that music and video content require different placements. The ITU standard states that the left and right speakers are located at ±30°, while the rear speakers should be positioned approximately ±110°. There is speculation that rear loudspeakers at ±150° provide "more exciting surround effects".
