AC3 Dialog Normalization - needed at all?

[rezonat0r]

I've read the guide (http://forum.doom9.org/showthread.php?s=&threadid=56020) on properly encoding AC3, but I still have one point of confusion...

If I completely turn off Dynamic Range Compression (DRC), does this mean that the Dialog Normalization setting doesn't matter and can be ignored? I am dealing with 2 channel audio (would the answer be different with 5.1?)

I work with alot of audio tracks at once, using SF's Batch Converter to normalize all the files first. It'd be nice to not have to load each individually into Sound Forge and measure the RMS for the dialnorm value.

So can anyone confirm that with DRC turned off the dialnorm is ignored and the sound is as unaltered as possible? Thanks a bunch!

[SomeJoe]

No. Turning off DRC will turn off boosting of low-volume sounds and attenuation of high-volume sounds. However, the dialnorm setting applies a fixed attenuation on the entire sound file.

To make completely unaltered sound, you need DRC turned off, and dialnorm at -31 dBFS.

[rezonat0r]

Ah yes, forgot the magic -31 dbFS number. Makes sense. Thanks!