AC3 or MP2 Audio

[Art Vandelay]

I have a episode DVD that I authored from Sat. TV capture. 3 episodes on the DVD at compression 78% with DVD-RB/HCenc. I used ProjectX to demux the Mpeg I made with Sonic. Then used DVDAuthorGUI to author DVD files.

When I select the audio source for authoring I can select MP2 or convert to AC3. If I use MP2 the audio file is twice the size of AC3 and much louder. I have been using AC3 so more space is avaliable for the video (less compression). I have noticed that the audio is louder on the 2nd episode than on the first episode (both audio files are AC3). AC3 is at 48000 192 BITS, 2 channels. Might this just be a TV network thing from when the capture took place?

[anonymez]

Might this just be a TV network thing from when the capture took place?

Probably. TV networks (in Australia, at least) adjust volume for all programming so it's pretty much consistent.

[Art Vandelay]

Ok

Ok, yes probably HBO. But I tried authoring DVD files again but with audio as mp2 rather than ac3 and I notice the overall volume of the audio to be much louder than with ac3. The file size of the mp2 file is twice the size as the ac3 file. Any idea why the volume would be higher than the same audio as ac3. Both formats are 48000, 2 channels, 192 Bits.

[anonymez]

Unless your decoder is normalizing (and you can check by playing the audio with VLC or Media Player Classic and comparing), it is a problem (if it can be called that) on their end.