AVI or 2ch AC3 to 5.1 Surround AC3

[Mickey79]

Ave,

Is it possible to convert a normal AVI file audio to 5.1 Surround AC3 ? Or basically to convert mp3, wav, or 2 ch AC3 to 5.1 AC3 ?

I use BeSweet for all my AVI -> AC3 conversions. I recently purchased a home theater system which outputs 5.1 surround dolby digital, it has multiple speakers and all.

I want to encode my audio to 5.1 AC3 instead of normal 2 ch AC3. I read something about 'Matrix Mixer', don't know much about it.

Anyone got any suggestions?

Thanks,
Mickey

[mats.hogberg]

Why? You won't get 6 (different) channels anyway.

/Mats

[sammie]

Yes, it's possible, but it takes some work and the right tools. There are a few threads here, but there are some much more comprehensive ones at Doom9. Here is a good place to start, but look around there are several more there: http://forum.doom9.org/showthread.php?s=124aa48840e7ee8a42755b77130abbaf&threadid=85446

@mats.hogberg Mostly true, but!!! I started out just wanting to take advantage of the extra surround speakers and maybe split out a LFE channel, just to divide up the work more efficiently among my speakers. But with a little creative filtering it is actually possible to create a great LFE channel, a reasonable center channel and surround channels that do a nice job of "filling" the room with sound. On some movies you can actually add some decent ambience that creates a good sounding surround effect. This obviously works much better on something like a concert where there is a set focus and no real movement of the sound. You can then apply pre-made filters for say an appropriate concert hall echo and delay. Now, that isn't the "true" sound track, so I usually include a plain old normal stereo MP2 track when I play too much with the sound. But it's a rare sound track that you can't improve somewhat by splitting a LFE and center channel.

Is it always worth the work and extra bandwidth for sound? Nope, but it's a fun exercise for many movies. Just don't fix up an old Boggart or Bob Hope soundtrack

[daphy]

yes, it´s possible -> see the doom9 link. But this is only one method, there are many more on 'needfulthings', I also did a flash guide for better understanding 8)

so, feel free dig there for solutions!

BTW: AC3 as sound format, okay but where? inside a AVI or a VOB/IFO container or as single file (AC3 can be replayed by the most stand-alone divx player)

[sammie]

Yes as daphy said there are several approaches. The thread I pointed to discusses some has lots of links to others and starts out discussing probably one of the simpler ones.

@Daphy thanks for gathering the basics together at one site too BTW!

[winifreid]

Sammie, which one of those methods do you use? It looks like it could get pretty expensive. I can't really tell if Bidule is freeware since it says to unlock costs $75. It appeared Bidule was the preferred program. I assume the others are not free either. I know audacity works with vst plugins, but I assume not with these. How easy is this? Do you just demux, load it into Bidule and let it rip (after you have setup some sort of template)? Then mux and author? It would seem very easy to get sync issues.

[sammie]

I use some of each. I started using Cool Edit and followed on through with Adobe Audition as it updated. I've also used Bidule and you are right it is now payware, it's free for 30 days but the old beta versions were free. If Audacity works with VST plugins you can probably do quite a bit. The only thing I'm not sure about is does it handle 5.1 audio? You can still do things one channel at a time then mux them with BeSweet.

Bidule is probably both the easies way to go to start and possibly the better high end. Audition is probably a bit easier to use as you pass through the middle of the learning curve IMO.

One other suggestion. Adding "presence" or "wet" or "ambience" is kind of like sharpening in video processing. It sounds great and cool at first, but a little goes a long ways and you will probably tend to overdo it at first because it sounds so different. Save your original 2-channel unaltered .wav files files because you'll probably find in a few months you will want to go back to some of those originals and tone it down a bit. If you save the originals you won't have to go back and re-sync everything. Then once you start getting happy with your mix and developing a more educated ear you can stop doing that.