Digital 5.1-channel audio is a discrete multichannel surround sound system.
Discrete means that the sound information contained in each of the six
available channels is distinct and independent from the others. These
six channels are described as a "5.1-channel" system, because
there are five full-bandwidth channels with 3-20,000 Hz frequency range
for front, center, and surround, plus one "low frequency effects"
(LFE) subwoofer channel devoted to frequencies from 3-120 Hz. Dolby Digital
is transmitted as a digital signal, like CDs, rather than an analog signal,
like a VHS video track. This makes for a clearer, richer sound.
Digital features stereo surround channels: you can hear separate off-screen
sounds to the left rear and right rear simultaneously! And with five full-bandwidth
channels and a dedicated subwoofer channel, Dolby Digital is capable of
delivering much deeper bass than Pro Logic. The discrete nature of Dolby
Digital means that sounds can be placed much more precisely, for improved
dialogue clarity, soundstage size, spaciousness, and realism.
Dolby and the double D symbol are registered trademarks
of Dolby Laboratories.