Dolby Laboratories CP650, Руководство по установке

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Dolby
®
Model CP650 Installation Manual Format Definitions
D-6
Format 74
Video Pro Logic No SW Nonsync 1
Short name: Vid Pro Logic No SW
Audio Description: This external audio format has two discrete input channels (L, R)
and is input through the Nonsync 1 input connectors. The audio is processed with
Pro Logic decoding and output on channels L, C, R, with a mono signal to Ls and Rs.
There is no derived subwoofer.
Format 75
Video Pro Logic with SW Nonsync 1
Short name: Vid Pro Logic +SW
Audio Description: This external audio format has two discrete input channels (L, R)
and is input through the Nonsync 1 input connectors. The audio is processed with
Pro Logic decoding and output on all channels. The subwoofer signal is derived by
summing L + C + R (after matrix decoding). This audio is then sent to the user-
selectable 50 or 100 Hz subwoofer filter, and the output level is controlled by the
separate optical subtrim. As in optical formats, the level is nominally set to match the
passband level of the center channel using an RTA.
Format 80 (Cat. No. 790 or 778 required)
Bitstream Master Digital Input
Short name: Master Digital In
Audio Description: The input is a digital bitstream into the Option Card I/O
connector, AES 1 (L/R) pins. This format automatically detects whether the bitstream
is PCM or Dolby Digital (AC-3), and configures the decoder appropriately. For a
PCM (two-channel) input signal, matrix decoding may be applied using the “Format
80/81 PCM Options” screen. This screen also contains a “PCM Auto Mute” option
that causes the CP650 to mute automatically if it does not detect a Dolby Digital
bitstream. This prevents noise when working only with encoded bitstream audio. For
Dolby Digital bitstreams, the metadata contained in the bitstream specifies the
channel format and surround processing to be applied.
This format does not support more than two channels of PCM. For multichannel PCM
support, use formats 88, 89, or 90 (see below).