What kind of AC3 is it? either, reporting, however, telling, number

andy

I have an AVI file that has AC3-2.1 in the filename.  With GSpot it's telling me it's AC-3 Stereo.  Is it really 2.0 or is GSpot not reporting the audio correctly?  If not, how do you tell for sure?  Thanks.

JR

No such thing as 2.1. Load the avi into VirtualDubMoD and check File -gt; File Information. Under Audio Stream, check the number of channels.

Thanks!!  I didn't think there was either, however Sonic Soft Encoder seems to feel it's an option when encoding.  It has an option quot;2/1 (L,R,l)quot; for Audio coding mode.

Don't mistake the quot;/quot; with the point quot;.quot;
X.1  -gt; LFE present
X.0  -gt; LFE not present

From Sonic Foundry Help:

Dolby Digital channel designations

1/0Center
2/0Left, Right
3/0Left, Center, Right
2/1Left, Right, Surround
3/1Left, Center, Right, Surround
2/2Left, Right, Left Surround, Right Surround
3/2Left, Center, Right, Left Surround, Right Surround

LFE enable

This option enables or disables the encoding of the LFE or Low Frequency Effects channel. This channel is typically used as a sub-woofer channel.
The LFE channel is only available with 3/0 mode and higher, therefore this option will not be available in the two-channel version of Soft Encode.

Ahh.  Interesting.  So when do you use the x/1 quot;Surroundquot; setting as opposed to x/0 setting?

Well, 2/0 is plain stereo... 2/1 has, as shown above, an added mono surround channel - very rarely used.