AC3 recording


I asked this before but had no takers.
I want to record the Dolby digital being sent out of one soundcard (orriginal stuff, not pirating) in through a Delta 1010LT. What do I need software wise to do it right?

The title may be throwing folks off or we don’t understand what you want to do.

To record from one soundcard to the other all you need to do is send the output of one to the inputs of the other, and be vary careful you don’t setup a feedback loop.

AC3, being an encoded format, means it needs to be played and you can record the audio, but you can’t record into AC3 on the fly or keep it digital all the way. I’m pretty sure you’ll have to do an D/A-A/D conversion. Dolby is pretty strict about what it lets happen in software.

Send the 6 out channels to 6 inputs (might be 3 stereo pair) and record them as 6 mono track. Once you have the 6 mono tracks you can then load them up into an app that lets you encode to AC3.

I’ve us Sonic Foundry Soft Encode, but it’s a really old app and not available any more. But, Adobe Audition 1.5 supposed it I think. I just got that and have started to play with it. I don’t need to encode very often so I don’t know as much as I should about AC3.

I don’t want to record something that started as ac3 and is being sepparated, my card is taking three stereo signals and encoding them as dolby and I want to be able to record the encoded signal from the digital out into the digital in of my other card as the dolby stream.

What are you trying to achive in the end? I don’t understand why the second bounce from digital to digital if you already have it recorded.

Right Bubba.

Just copy the file to the machine you want to get it to.

Anyway, AC3 is an encoding. What you are asking to do isn’t limited to AC3. It could apply to any encoded format - MP3 WMA OGG. All you are asking for is a digital transfer. That can be done with a file copy across a network or by burning it to a data CD, or to a floppy if it’s small enough. There’s no need to use spdif for that.

Now, if you are trying to capture direct digital out from a DVD player then you may be out of luck. Some players can send the digital signal to TVs or amps that had digital inputs. The receiving end has built in hardware decoders for playing the audio. This is what I meant by Dolby having a tight grip non what can be done. I don’t think Dolby will allow that to be done in software, except in the case of playing a DVD on the computer. In that case there might be a software decoder, or it might be in hardware on some cards – look for AC3 Decoder in Hardware in video cards.

I still don’t know what your aim is. Exactly what are you trying to do? Sounds like you are trying to capture the audio from a DVD player (or non PC device) via the digital out.

The first sound card encodes on the fly, I don’t end up with an encoded file, but that’s what I want to do. I’m mixing stuff I recorded, and letting the card encode it to stream out of it’s digital out, but I don’t have a file I can play on anything other than Ntrack.

I think I see what you are running up against.

I think you are looking for something that doesn’t exist (except illegally maybe), but would also be better accomplished in a different way.

What you need is software that will take 6 submixed tracks and encode them to AC3. Adobe Audition 1.5 will do it. That’s what I use. Sonic Foundry has some apps that will do it but you need their 5.1 Encoder plug-in. (It’s proprietary to add functionality to their apps that support it - not a dx or vst plug in). And Sonic Foundry Soft Encode will still work if you can find it (I used that too, but not since Audition supports it now - nice graphic positioner).

I don’t know of any card that will capture a digitally encoded Dolby stream straight to a file. That’s the kind of stuff Dolby won’t allow. You can hook that output to some devices like TVs that accept it and they will decode and play it.