Lexicon Lexicon Part #070-13234 AC-3 Effects and 4 AC-3 EffectsParametersnd Parameters

DC-1 Version 4 Digital Controller

AC-3 Effects and 4 AC-3 EffectsParametersnd Parameters

AC-3 effects are compatible with Dolby Digital input signals. Any AC-3- capable software and/or source components should be labeled with aDolby Digital badge, similar to the one on the DC-1 front panel.

In the AC-3 effects, an AC-3 Status Display is available in the parameter AC-3 Status Display 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 andS=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 = -14dB and the DC-1 would adjust the levels down 4dB to bring dialog back to -31dBFS.

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