Noobie needing help getting AC3 sound ....

[SomethingClever]

Ok so i've made my divx, joined the AC3 audio track and Divx video and everything looks and works perfect.

Except i'm not getting true AC3 audio. I tried to follow the guide as closely as possible but there must be something im not following on how to install the codecs or something. I am using PowerDivX to view my movies and its set up for 4 speaker output.

Could someone quickly run me through what I have to do as far as setting up my system to playback AC3 audio with Divx. I have a Santa Cruz soundcard along with the Klipsch 4.1 that I am using for dvd viewing.

Thanks

[MaTTeR]

Have you read the AC3/SPDIF FAQ yet? Have a look at my sig.

[SomethingClever]

Yes i did read it. There must be something i'm not getting. I'll try to simplify it alittle for myself and try it again. Hopefully i'll get it this time.

[MaTTeR]

Have you tried playing the AC3 file by itself?
Have you installed the proper filters for AC3 playback?
What part of the guide is confusing for you?
Are you getting errors during playback? If so what?
Which players are you using?
Is the Klipsch 4.1 for the PC or is it hooked to an external amp?

Please be more specific with what your problem is so we don't play a guessing game. Just telling us that it doesn't work won't help much;)

[SomethingClever]

ok so this may help .. as far as I know i've installed the codec because I can play AC3 files. I can haer sound in my divx movie with AC3 sound but it feels like its playing in 4 speaker stereo meaning that the front and rear speakers feel as if they are playing the same thing.

[MaTTeR]

I repeat yet again:rolleyes:

Which players are you using?
Is the Klipsch 4.1 for the PC or is it hooked to an external amp?

Also, have you checked the filter properties to see if it's set for 4ch or 6ch mode? What is your sound control panel set to for speaker selection?

[SomethingClever]

Sorry about the confusion, i've got encoding Divx down to 2nd nature but this AC3 stuff is very new and I wanna get it down.

1.) Yes I can play the AC3 file by itself in Windows Media Player. It doesn't sound like true 5.1 audio but it does play.

2) I believe i've installed the proper filters. I followed the AC3 Q&A and I DL and registered the audiofilters file. I unzipped them to their own folder and registered them. Do I have to physically move these files somewhere? Windows/system folder or something?

3) Maybe the guide isn't so confusing as the problem is I feel there must be another step I am not doing. Maybe I haven't installed the files correctly yet.

4) No errors whatsoever during playback. Everything sounds fine.

5) I was using Windows Media player b4 but when I installed Divx 5 all my movies were async for some reason. I downloaded PowerDivx and my movies play normally there. I went into the audio config there (AC3 audio tab) and set the tab to 4 speakers mode since I am using a 4.1 speaker system.

5) The Klipsch 4.1 is for the PC ... it's a dedicated computer speaker system designed to be used for PC. For watching DVD's i'm downmixing 5.1 sound so that i'll get the 5.1 experience with my 4.1 system here.


Thanks for the help!

[MaTTeR]

Ok, so now were getting somewhere:)

It looks like you have done everything properly so far. If the filters were not installed properly then you would not hear the AC3 at all.

So it seems to me that your speaker software setup might be causing the problem. Could be the sound control panel is only set to 4 speaker mode instead of 4.1. Check this first. When you change the speaker setup in PowerDivx to say stereo(2ch) do you hear a difference? After changing speaker settings in PD, you may have to quit and open it back up for the settings to take effect.

Sound control panel-
Star Menu->Control Panels->Sound blah blah

[SomethingClever]

Wait, just to make sure my process to join the Ac3 and Divx correctly was correct i'll explain how I did it. I guess it was nothing glamorous, I just threw the AVI and AC3 into NANDUB and multiplexed following the guide from Doom9.org

[MaTTeR]

Originally posted by SomethingClever
Wait, just to make sure my process to join the Ac3 and Divx correctly was correct i'll explain how I did it.

This is the easy part:) Are you sure it was a 5.1 AC3 file though? Just curious.

[SomethingClever]

Yea, thats what I was thinking. If it wasn't installed correctly I shouldn't be able to hear it.

Whew, ok so .. I went into the sound control panel. I've got it set to Quadrophic speakers which i'm thinking is 4 speaker. Also in my Santa Cruz control panel its set to 4 speaker output. (I don't think this is my problem since I can use PowerDvd to view Dvd's in 5.1 glory.)

Ok i'm changing my speaker setup in PowerDivx in the AC3 tab from stereo to 4 speaker and nothing seems to be happening. There seems to be no real change in sound quality or anything. This seems alittle wierd. I've quit and opened it back up .. no change.

[SomethingClever]

Originally posted by MaTTeR


This is the easy part:) Are you sure it was a 5.1 AC3 file though? Just curious.


I am almost 100 Percent sure it was an AC3 file. I ripped it from the DVD using Smartripper and I chose the 6 channel AC3 track. And when it was ripped the filename had AC3 in it.

[SomethingClever]

ok wait i've got something here ...

I've ripped the Hannibal DVD and I have the AC3 track. I put that into PowerDvd and it plays in 5.1 sound. I put my Memento AC3/Divx concoction into PowerDvd and it just plays in 4 speaker stereo.

So something must be happening with my while i'm joining my Ac3 track and Divx file. Although I don't know what.

[MaTTeR]

I'm not so sure about the Quadraphonic. That doesn't sound correct for a 4.1 system but I could be wrong.

Anyway, if your PowerDVD sounds good then what do you have it's audio configuration tab set to? Why not try and play and your AVI in PowerDVD since you know it plays 5.1 properly?

Please understand an AC3 file could be 2 channel or 6 channel. Because it's an AC3 file doesn't mean it contains 6 discrete channels of audio. The filename will always have AC3 in it. However, since you selected the 6ch stream in SR it should be correct.

[SomethingClever]

In order to join the avi and AC3 track I used this guide from Doom9.org Ac3/Divx guide (http://www.doom9.org/divx__ac3.htm). I didn't do anything concerning Graphedit or anything though.

[SomethingClever]

In PowerDvd, in the audio tab i've got it set to 4 speaker output so that it will downmix the 5.1 audio to 4.1 so that i'll get 5.1 sound out of my 4.1 system. It's creating a "phantom" center channel with my 2 fronts so i'll get almost the same effect as a true 5.1 system.

[MaTTeR]

It sounds like your AC3 filter playback is set incorrectly.

When playing the movie in PowerDivx, right click on the movie window and select filter properties. Double click Intervideo Audio Decoder, select 4 speaker mode and see if that sounds any different. I think it sets itself to stereo mode by default.

[MaTTeR]

Your issue has nothing to do with muxing the AC3 in to the AVI. If it was a 5.1 file going into NanDub then it will be the same after muxing.

[SomethingClever]

AHHHHH WE ARE GETTING SOMEWHERE NOW!

I see the Intervideo Audio Decoder in the filter properties (which i never thought of touching) but I cannot choose 4 speaker output. I think this is my problem because it is set to stereo. I can however set it to SPDIF output although that doesnt help me. I need to get that to 4 speaker.

I also have an mpeg layer 3 decoder in ther by default. Is that supposed to be there also?

[SomethingClever]

Hannibal AC3 T01 3_2ch 448Kbps DELAY 0ms ... thats the name of my Hannibal AC3 file. Which was the same format as the Memento Ac3 file that I finished earlier.

[SomethingClever]

I hear you about the muxing. Thats what I thought should happen.

[MaTTeR]

Originally posted by SomethingClever
Hannibal AC3 T01 3_2ch 448Kbps DELAY 0ms .
3_2ch indicates this file is 6 channels. If it said 2_0 then obviously it's just DPL 2/0.

I also have an mpeg layer 3 decoder in ther by default.
This appears to be normal operation using PD 3.12.

cannot choose 4 speaker output.
This is most likely the issue. Bad news is I can't select 4ch in my system either:confused: Let me try a few hacks and see what I come up with...

[SomethingClever]

This is very wierd. I'll see what I can find here also.

[SomethingClever]

Ok, so i downloaded the latest version of BSplayer. I can load the audio file fine and it just plays in 4 speaker stereo. There is an option in the menu for 4 speaker output which would give me 5.1 sound but when I start the movie it's only in 4 sp stereo. There is the menu for the intervideo audio decoder but again i cant select 4 speaker output as it is greyed out.

[MaTTeR]

Maybe you should download the Multi-Channel version of WinDVD. Apparently these AC3 filters were using dont support analog Multi-Channel.

[SomethingClever]

Geeze this is driving me nuts. I'll find Windvd and see if that helps.

[MaTTeR]

Not just WinDVD, there is a Multi-Channel version you need to get.

You might also dig around the Home Theater forums.
http://www.avsforum.com/avs-vb/

To be honest, I haven't seen to many 4.1 setups so this is why I can't help as much.

[SomethingClever]

I'm downloading Windvd 3 Fullversion w DTS decoding right now. This may be interesting. Although ... 60 megs on a 56k. Ohh this is gonna take awhile. In another 4 hours i'll be able to test it out. Lol

[SomethingClever]

Thanks for all your help till this point though. At least i know whats wrong! Yea the 4 speaker setup is limiting me quite a bit ... which is why once I move back home after this semester i'll be working on building a HT system. I'll be using this PC as a HTPC so i'll be able to just output the signal via the digital output to my reciever. But i'd like to figure this out if possible.

[MaTTeR]

I don't think the DTS version is going to work either. It's worth a shot I suppose...then again at that speed I dunno:D

I recall seeing a specific version call Multi-Channel, not DD or DTS. Hope it works for you.

[SomethingClever]

well, 40 megs downloaded so far ... LOL

I guess we'll see what happens. It would be nice if it worked. In any case i'll be happy to have the DTS capabilities on my computer for Dvd's.

I'll try to find that multichannel version also if this doesn't work.



:D