A surround sound processing technology that can extract center, left, right, bass and stereo surround channels from a stereo source. Pro Logic IIx can additionally extract two rear surrounds from either stereo or 5.1 sources, and Pro Logic IIz further extracts front stereo height channels.
Multiple modes may be offered by the system: Movie mode, Music mode and Game mode.
PLII works fundamentally as a matrix decoder with servos that accentuate the directionality of the current determined dominant signal by negative feedback in the other channels. The surround channels are fed by signals of inverted phase while the height channels contain uncorrelated, ambient signals.
Although PLII works from basically any stereo source, stereo programmes can be specifically encoded for surround decoding by PLII with matrix encoding. These programmes may be branded with the "Dolby Stereo" or "Dolby Surround" logo.
DO NOT believe Eazy-X's definition. It sucks so bad.
"This song is encoded by Dolby Pro Logic II!"
"No, Pro Logic II is a decoder only."
A system that splits a stereo signal into a 5.1 surround sound system. Since stereo recordings are made for 2 speakers and 5.1 surround sound systems have 6 speakers dolby pro logic II splits the different sounds into different speakers based on the wave length of the sound within the recording. Normally the vocals fall into the front center speaker and the instruments may fall into surrounding speakers and the bass falls into the sub woofers. many video game developers make games using dolby pro logic II technology because there is no digital audio outsource for the game device except some of the newer systems such as the ps3 and xbox 360. games that use dolby pro logic II will have sounds fall into an individual speaker based on where the sounds of gunshots or effects is located in relation to the perspective of the gamer. cd's are only available in stereo and dvd's could hold up to 7.1 surround sound. with dolby pro logic II stereo recordings could seem to have as much depth as a 5.1 recording.
some albums are recorded with dolby pro logic II in mind. notice how the main vocals falls into the front center speaker and the choir falls into all the surrounding speakers.