STEREO
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.
MONO
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.
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