I really want to understand the Dolby Digital LFE channel from both a recording and a playback perspective. I've been doing some reading of past threads and I'm as confused as ever.

The confusion is, of course, surrounding the +/- 10dB issue. I've skimmed through a couple of Dolby white papers and I'm still in the dark. So...

1) What level should the LFE channel for movies be recorded at vs. the other channels?

2) What level should the LFE channel for music be recorded at vs. the other channels?

3) What level is the LFE channel calibrated at in the playback system vs. the other channels? Edit: It appears that the LFE channel is calibrated for +10dB response vs. the other channels at the mixing desk.

4) On playback, does the DD decoder alter the LFE channel level by 10dB?

5) The Dolby spec. apparently requires +10dB to show as 0dB. Does the "Cinema" DSP preset alter LFE levels or just what is displayed?

6) The "Discrete" DSP preset sets the LFE channel to -10dB. Does this correspond to any actual change in the LFE levels?

7) Did DTS follow Dolby's lead in an identical, or similar way?

8) What happens to the LFE level in the DTS decoder?

Please: No speculation in this thread. Only reply if you actually know the answers.

Thanks in advance,
Joel

Last edited by VirusKiller; 2008-06-11 12:42.
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