Dolby Surround

Dolby Surround is the original consumer matrix-encoding format, embedding a single rear surround channel into a standard two-channel stereo mix via phase-shifting. Introduced to gaming during the fourth and fifth generations, it allowed developers to create early 3D spatial awareness using standard analogue RCA cables. When decoded by a Dolby Pro Logic receiver, the matrixed rear signal is extracted and sent to monaural rear speakers.