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Dolby Digital
Dolby Digital is a digital multi-channel surround system
which was developed specifically for spatial sound re-
production in connection with 35 mm cinema films. The
process utilises five separate sound channels: three front
channels (left, center, right) and two surround channels.
A sixth independent bass effect channel is also present,
catering for low frequency effects (
LFE
). That is why
such systems are said to offer
5.1
channels.
In comparison with Dolby Pro Logic II, Dolby Digital pro-
vides two independent surround channels which provide
genuine spatial stereo sound, offering the same realistic
stereo reproduction as provided by the front channels.
The decoder’s integral Dolby Digital decoder provides
the means of obtaining a genuine digital Dolby stereo
cinema presentation in your own living room. The dis-
crete digital recording process and the five playback
channels guarantee a very wide dynamic range and
accurate spatial orientation.
dts Digital Surround
The “
dts
” multi-channel film sound system was originally
developed to replace analogue film soundtracks, using
digital soundtracks consisting of six discrete channels.
This system has now been further developed to provide
spatial sound reproduction in the home situation.
The six channels (
5.1
) are encoded / decoded in original
quality, i.e. with 20-bit resolution, and recorded using
only slight data compression. The 5.1 loudspeaker con-
figuration, currently the standard arrangement for home
cinema systems, is ideal for playback.
Sound field simulation
The surround processes already described require pro-
gramme material which is encoded using the appropriate
system, but the digital surround decoder also offers a
facility to enhance the spatial effect available with con-
ventional unencoded stereo recordings (CD, MC, VHF
radio etc.).
This it does by offering a range of artificial
sound field
simulations
, including theatre, stadium, club etc.
These sound fields are based on a precise analysis of
the acoustics found in typical concert halls.
The digital signal processor of your digital surround de-
coder is capable of simulating the spatial sound of these
halls, and reproducing it via the five channels of your
surround system.
For example, if you select the
HALL
setting while
watching a rock concert on television, you will have the
illusion of sitting in the middle of the audience.
Please note that it is important to set the sound field
which is appropriate to the material to which you are
currently listening. It makes no sense at all to select a
sports stadium if you intend listening to a concert of
chamber music, or an intimate club atmosphere for a
rock concert.
Your digital surround decoder can generate the following
sound fields:
HALL
THEATRE
STADIUM
CLUB
CHURCH
DISCO
