10. Stereo and Stereo Downmix Mode
If this button is selected and the supplied bitstream is more than 2 channels, the
decoder will automatically implement a stereo downmix. Otherwise,
analog or digital two channel signals are passed as conventional stereo.
11. Mono and Mono Downmix Modes
If this button is selected and the supplied bitstream is more than 1 channel, the
SP1.7 software will create a Mono mix of all signals. If the centre channel is
present, the Mono signal will appear in the centre channel. If no centre channel
is present, the mono signal will appear simultaneously on the Left/Right speakers.
NOTE: Downmix [stereo or mono] is a software based automatic mixing
function available within the SP1.7. This process exists because whenever the
number of active decoder outputs or loudspeakers selected in setup is less than
the number of channels in the Dolby Digital program, some channel combining will
be necessary to present the program on the available number of
channels/loudspeakers.
As a part of any program’s production, its producers can set and adjust the type
and ratios allowed for downmixing somewhat to ensure optimum results without
compromising the full Multichannel balance. This is accomplished by including
specific data within the Dolby Digital bitstream which represents different mix-
ing coefficients for the centre and surround channel signals.
These will be detected by the SP1.7 and used to produce the downmix if this
mode is selected.
8
STEREO
MONO