AC3 Dialogue Normalization in Vegas

[W_Eagle]

Movies captured from Satellite and Cable TV into avi files -- I have few captures daily. From the avi files I encode the audio into AC3 with Sony Vegas 5.0b. For one thing, I don't need any compression, as the audio files are compressed already by the broadcasters. However, audio levels of various movies have marked differences, so I cannot use a simple preset audio volume setting. Also, I'd like the dialogue level to be similar to that of most commercial DVDs, so that I wouldn't have to play with the HT amplifier volume too much between different movies, commercial DVDs and home burned DVDs. What I do so far is to browse some dialogue parts of the captured movies and set the audio volume in Vegas for dialogue peaks between -18 to -15 dB. This is quite tedious and not very accurate, as there are level differences between different dialogue parts.

The video from the avi files is encoded to mpeg2 by TMPGEnc XPress. Than, the m2v and ac3 files are authored by TDA.

Is there a simple way to automatically normalize audio, or dialogue level, in Vegas? Please, I don't use Soundforge. I will use it, should Vegas cannot do it in a simple way and should Soundforge be able to do what I currently use Vegas for -- extract pcm audio from the avi files and encode it to ac3.

In Vegas, in Default Audio Template, in Audio Service there is a field for Dialog normalization -27dB. I wonder if it does actually normalize the dialogue level, and if does so when Bypass All Audio FX is tagged. I bypass the Audio FX since I don't need any compression and I don't know how to set the compression, without bypassing it, so that the audio will not be compressed further.

[Silvas]

Right click on audio clip, select switches, then normalize.

silvas

[BJ_M]

Dialog normalization in ac3 is not normalization of the audio program material ....

the amount of compression is set by the bitrate and nothing to do with the normalization settings ...

do as silvas says -- and set Dialog normalization to -31dB in ac3 settings ...

for more info - see vegas manual or go to dolby site where there is a ton of info on this ...

[W_Eagle]

Thank you both, Silvas and BJ_M.

BJ_M, as far as I understand (being a sound engineer many years back), the audio level compression has nothing to do with bitrate -- it is about reducing the level differences between the loud parts ans soft parts of the audio track(s).

I did some reading on AC3 dialogue normalization in various places -- it is both over my head (though I'm a technical person) and beyond my humble needs. I don't need to do it in accurate scientific way. I author few movies a day, on 2 different computers. All I need is a quick and simple way for setting in Vegas the audio level of movies, each captured at different audio level, so that the various movies' audio level will be of similar magnitude -- and similar magnitude to that of commercial DVDs.

So, my question is: Will it do what I need?: Right clicking the audio clip, selecting switches and selecting normalize, Dialog normalization -31dB, while All Audio FX are bypassed?

[BJ_M]

yes -- that is what you need to do ....


the dialogue normalization in ac3 encoding is SUPPOSED to do the same thing -- but in practise , dolby decoders (and users) just notice that ac3 is always quieter... by setting it to -31, you effectively bypass the dolby reduction of volume ...

you do the normalization yourself via the method outlined above in vegas - in which you do all the tracks

[W_Eagle]

yes -- that is what you need to do ....

you do the normalization yourself via the method outlined above in vegas - in which you do all the tracks

Thank you. I looked over Vegas Manual (pdf) over and over again, but couldn't find the procedure for dialogue normalization. What do I need do after right clicking the audio clip, selecting switches and selecting normalize (when Dialog normalization is set to -31dB)?