In PowerDVD when the disc is playing right click on the window and select Show Information which will show the current audio format (and time, etc).

One of the control buttons, if you hover over it, is called Next Audio Stream.  Click that button to cycle thru the Audio selections.  This will work for most discs but some discs only let you change them from the DVD menu.

Other programs can be downloaded and will provide the same info.  Nero Info Tool (don't know if you need to by Nero for this), DVDFab.  There are others.

Quoting tweeter:

Quote:
Nero Info Tool (don't know if you need to by Nero for

Nope, it's free 

Cass and others

Be careful. Most software, including PowerDVD is going to give you a DD 2.0 reading. That means NOTHING. There is Dolby Digital 2.0 Mono. Dolby Digital 2.0 Stereo and Dolby Digital 2.0 Surround. It gets ugly very quickly.

Mono and Stereo can best be judged via graphical analysis of the audio data. I know of nothing that will give you that answer. DVDShrink will read the tracks and tell you if it has a Surround flag encoded, it will report 3 tracks, while Stereo would report 2 tracks.

Skip

Quoting gardibolt:

Quote:
Quoting skipnet50:

You can distinguish mono and stereo pretty readily by playing the DVD on a player through a receiver that has Dolby Pro Logic engaged.  If it's mono, you should get nothing out of any speaker except the center speaker.  If anything is coming out of the left or right or surrounds other than hiss, then it's either Stereo or Surround, and then do as Skip said to tell those two apart.

Skip was referring to two-channel mono.  The packaging will usually say it's mono but the audio decodes to 2.0.

Being DD 2.0 can make the Mono tracks rather non-obvious.

Quoting tweeter:

Quote:

Skip was referring to two-channel mono.  The packaging will usually say it's mono but the audio decodes to 2.0.

Being DD 2.0 can make the Mono tracks rather non-obvious.

As gardibolt already said, it's easy to find out whether the audio is two-channel-mono or -stereo. Just send the signal through a ProLogic decoder. When the sound only comes out of the center, it's two-channel-mono, otherwise it's stereo or surround.

Caleb:
This is not a hard fast Ruel, but a Rule of thumb, in my experiencei if you are dealing with a Contemporary DD.5.1 track and have a Commentary, it will more than likely be DD 2.0 SURROUND. That's about as close as I can come. Ilearnned a long time to keep my computer equipped with an array of tools for Audio work.

Skip

Quoting skipnet50:

Quote:
Caleb:
This is not a hard fast Ruel, but a Rule of thumb, in my experiencei if you are dealing with a Contemporary DD.5.1 track and have a Commentary, it will more than likely be DD 2.0 SURROUND. That's about as close as I can come. Ilearnned a long time to keep my computer equipped with an array of tools for Audio work.

Skip

A wise man told me, that if you can hear the original score in background than it's always surround, because the original score is normally at least 4-channel-surround (e.g. Dolby Stereo -> Left Center Right Surroundmono))
And even an additional mixdown to 2.0 again wouldn't eliminate the matrixed surround-sound (from the score in background).

So if it's not Mono it should be 2.0 Surround

Quoting madacid:

Quote:
A wise man told me, that if you can hear the original score in background than it's always surround, because the original score is normally at least 4-channel-surround (e.g. Dolby Stereo -> Left Center Right Surroundmono))

eh ... as a standalone statement it sounds like utter nonsense.

What exactly is 'in the backgorund' and 'normally' supposed to mean in this context?
And what timeframe does this wiseman have in mind? I hear OST in the background on "The Wizard of Oz" (1939), but you wouldn't suggest that it had a 4-channel-surround audiotrack?

And why shouldn't any DVD-authoring-tech simply convert anything with more channels down to stereo? We've seen stranger things in the last ten years.

cya, Mithi