AC3 audio bitrate

[44echo]

I've read from multiple sources that the bitrate for AC3 audio is 448 Kbit/s. From this newbie's point of view, that seems kind of high for compressed audio. It seems like it would take up too much space for just the audio. Especially when I want compressed audio so I can get better video.

If I start with DV-AVI and wish to convert to MPEG-2 for DVD authoring, I need to use 448 Kbit/s when using the bitrate calculator?

How come my audio is listed (with AVIcodec) as 192 Kbit/s after Nero converts it? Can I use 192 Kbit/s when using the bitrate calculator?

Thank you.

[guns1inger]

The bitrate for AC3 varies depending on who authored it, how many channels it has, and the quality of the source. Many commercial disks are authored with 5.1 channels at 448, but many are authored at the slightly lower 384. For most home setups you would be hard-pressed to tell the difference. If you are encoding only two channels, then 192 is about right. If they are particularly high quality, then you might go up to 228.

For my authoring, I use 384 for 5.1 and 192 for 2.0 (and even 2.1). Most of it starts with DV or VHS source, so the extra bitrate is wasted.

[44echo]

Previously, I would use encode with CCE (Aud+Vid) and then let Nero convert to AC3 when burning. I've got about 20 DVDs under my belt and it's time to move on to bigger and better things.

I'll still use CCE, but I'm want to get away from Nero for authoring DVDs. I want to switch to DVD Workshop. I also plan to start using variable bitrate encoding with CCE.

If I use the bitrate calculator and use 192 Kbit/s for the audio, am I then trapped into finding a way to convert the audio to AC3 192Kbit/s or risk it not fitting one a single DVD? Maybe that's a stupid question. I just want to make sure I understand this.

All video is home-shot from my Sony HC30.

Thank you.

[44echo]

If I use the bitrate calculator and use 192 Kbit/s for the audio, am I then trapped into finding a way to convert the audio to AC3 192Kbit/s or risk it not fitting one a single DVD? Maybe that's a stupid question. I just want to make sure I understand this.

Can anyone confirm this?

Thank you.