Lexicon DC-2 - Manual (Page 53)

45
DC-2 Digital Controller
AC-3 Effects and Parameters
4
AC-3 Status Display
AC-3 Effects and
Parameters
AC-3 Effects are compatible with Dolby Digital input signals. These effects,
along with the PCM Effects described in Chapter 3, are included in the AC-
3 and DTS versions of the DC-2. Any AC-3-capable software and/or source
components should be labeled with a badge, similar to the one on the DC-
2 front panel (AC-3 and DTS versions).
In the AC-3 effects, an AC-3 Status Display is available in the parameter
menu with the following information.
MATRIX ENCODED: YES indicates a 2.0 Dolby Digital input is matrix
encoded; No indicates it is not.
DOWNMIX: YES indicates a Dolby Digital input is being downmixed for
the selected speaker configuration. NO indicates no downmixing is taking
place, except in the 5.1 2-Channel Effect, which is designed to create a two-
channel downmix from Dolby Digital 5.1 channel signals.
DATA RATE: 32-640kb, depending on the data rate of the incoming Dolby
Digital signal.
SAMPLE RATE: 44.1kHz or 48kHz depending on the incoming Dolby
Digital signal.
PGM CONTENT: shows you the actual spatial characteristics of the incom-
ing soundtrack. The information appears as F/S.LFE where F=the number
of front channels and S=the number of surround channels. LFE=.1 if the LFE
channel is on.
For example, a given source may display 3/2.1, indicating that the source
was mixed with 3 front channels, 2 surround channels, and the LFE channel.
When the designation .1 indicates that the LFE channel is on, as in our
example, a level meter at the bottom of the display will show LFE channel
activity. (Note, that there may be instances where the LFE channel is on, but
no activity shows in the meter display.)
REF OFFSET indicates the Dialog Normalization value that is present in
AC-3 bitstreams. In AC-3, dialog is reproduced at -31dBFS (31dB below full
scale). If the program material was mixed so that dialog is at -31dBFS, then
REF OFFSET=0dB. If the dialog was mixed at a "hotter" level, for example,
-27dBFS, then REF OFFSET = -4dB and the DC-2 would adjust the levels
down 4dB to bring dialog back to -31dBFS.
AC-3 STATUS
DOWNMIX
SAMPLE RATE
DATA RATE
PGM CONTENT
REF OFFSET NO
48kHz
384 kb/sec
3/2.1
-4dB
MATRIX ENCODED NO
LFE