What is the default level of ac3 files?

Question

I am a long time Logic user, but new to Compressor. I was asked to supply an ac3 file to a dvd authoring company. I "successfully" converted from aif using Compressor, but the resulting file was at -20db, no matter what parameters I tweaked.
Is this "normal"? Why would adjusting parameters such as dialogue normalisation, soften over... and master gain have no effect on the outcome?
Each time I adjusted a parameter, I would save the settings, and then import them into the batch manager window, but I always ended up with an ac3 file at -20db.
Huh?

Answer 1

See if this helps.
a) Click your audio setting and have a look at the Encoder tab in the Inspector window.
b) Under the Audio tab, change the Dialog Normalization from -27 to -31 to disable it.
c) Click the Preprocessing tab and set the Compression Preset to None.
d) Deselect the Low-Pass Filter and DC Filter
*Compressor User Manual -> Creating Dolby Digital Professional Output Files*
Important: It is critical that you set the Dialog Normalization setting correctly if you intend to use any of the Compression Preset settings. The Compression Preset settings assume that the audio, after the dialogue has been normalized, is at the normal listening level of 31 dBFS. Levels that are consistently louder than that result in distorted sound and erratic levels.
If you do not know the sound level of the source file or for some other reason want to ensure the Dolby Digital Professional encoder does not affect your sound levels, enter –31 for the Dialog Normalization and choose None in the Compression Preset pop-up menu (located in the Preprocessing tab).