AC3 2.0 to 1.0

[mircx]

Hello

Does anybody know how to convert an ac3 2.0 stereo track (256kbps) to an ac3 1.0 (mono, center channel only) one? Ideally without recompress the track, something like combining the left and right channel into a single center channel.

Thanx.

[FlimsyFeet]

The only way to do it without re-compressing is to downmix to 1.0 on-the-fly in your DVD player or AC3 decoder. Unfortunately, although most have the option to downmix 5.1 to 2.0, but not many give you the option to downmix anything to mono.

So you will probably need to recompress. To make things even more complicated, I think that if you tell BeSweet to downmix 2 channel AC3 to mono wav it still gives you a 2.0 wav file (I could be wrong on that, but I remember something funny going on when I tried to do something similar.

So you will need to deocde 2.0 AC3 to 2.0 WAV, stick it in an editor like audacity to downmix to mono, then feed that mono wav into an AC3 encode like Aften.

[mircx]

Thanx for the reply.
I found another interesting way. It involves ac3filter and graphedit. I'll try tonight and report back.

Edit: Well, it works via Adobe Audition and ac3 plugin to save in mono which is correctly played on center channel. The only downside is the recompression.