Audio Passthrough

Nov 16, 2014 at 9:23 PM
I am considering using audio pass through for music dvd's, to get fullest sound quality, how much size does that add in general to file, compared to High Profile defaults, which I have been using.
Also, I have had a few dvd's where I wanted, and selected 5.1 but 5.1 was not present when compression completed, I generally have not had this issue, so I am unsure as to why? And yes I select 5.1 as my # 1 choice, have no problems on most discs with this. maybe I'm not understanding the ordering on the audio, if you have say, 3 audio options , and 5.1 is option #2, I select that, should that now be the main audio track? And if I add a track I can then chose, say the audio with commentary, then that becomes the second track?
Hope this makes sense....
Coordinator
Nov 16, 2014 at 9:50 PM
If you say that you want 5.1 surround sound, it will try to do it. Though sometimes the input source doesn't have 5 channels, in which case the choice will be grayed out and it will fall back to 2-channels.

It's hard to give you specific advice because I don't know what you're trying. When you say "Option #1 and Option #2" are you referring to the chosen tracks on the main window? Or the Audio tab in the encoding settings window? Screenshots would help.
Nov 16, 2014 at 10:08 PM
Audio tab in main window, the drop down lets you select whatever audio options are available: so if 5.1 1s the #2 option, and I select that, is that the audio option i should end up with?
Also, the other part, if I use passthrough and take the audio as it is on dvd, will that add a lot to the overall finished conversion file size, compared to just using the High Profile default settings?
How do i add a screenshot?
Coordinator
Nov 16, 2014 at 11:10 PM
The main window lets you pick which track will show up in the final encoded file. Choosing a 5.1 track is a required step in getting 5.1 channel output, but you also need to check the Audio tab in Encoding Settings. If you're using a Mixdown of Dolby Surround or Stereo, the output track won't be 5.1. You'll have to pick 5.1 channels or higher.

You should have a green box on the Audio tab with a preview of all the tracks you'll get in your final file. It should say Channel Layout: 5.1 if you've done it correctly.

As for passthrough, it all depends on what the input audio is. The raw audio from a DVD is often bigger than it needs to be, so you can usually compress it without too much loss. If you passthrough, it can add a fair amount to the size. You can experiment with small clips and see what you like.
Nov 16, 2014 at 11:55 PM
Dolby pro Logic II, high profile preset, is what I've been using...so i guess i haven't really saved anything in 5.1, misunderstood along the way?
Oh well, not like I really use 5.1, just center & sub, mainly want audible volume, sounds fine to me from what I've heard.
And I'm guessing mixing down to 5.1 adds space? hence not the preset...
Well, all I can say, is that for the hdd space saved, audio & picture quality, program works great, I need to get into the advanced tab i guess! But I am pretty happy with the high profile tab @17 CQ on pretty much everything.
Thanks for all the help
Coordinator
Nov 17, 2014 at 12:24 AM
Dolby Pro Logic II is encoding to two channels, but in such a way that it can tease it apart and create 6 channels again later. Encoding to true 5.1 will save all the channels separately and take up more space, but it will be better quality.
Nov 17, 2014 at 12:46 AM
Edited Nov 17, 2014 at 12:47 AM
Is Pass through in effect the same, I select 5.1 on main window, then pass through on the audio tab, I get 5.1, I think?

Thanks for explaining stuff, I did two different movie comparisons on just high profile then with pass through, the extra space was negligible, maybe that’s the change I’ll make.

All previous movies in Dolby pro II sound great, as I said I don’t use a full 5.1 system anyway, probably won’t, I’m just glad to have the volume with clarity, and for fake 5.1, sounds mighty fine!