I am not aware of any Adobe application encoding to AC3. I've never been fond of Audition, which is based on another piece of software they bought out and basically just renamed. The older versions never had AC3, so I'd be surprised if the Adobe renamed one did.
For AC3, you have a number of options. Free methods exist, and work great, although they are technically not 100% perfect AC3 files. However, the only time I have known them to be a problem is on Pioneer DVD players from about 5-6 years ago. I've been using AC3 from free methods for years now, and I've never had an issue, aside from the old Pioneer DV-333/334/444
Free software versions include:
(1) BeSweet with Besweet GUI and AC3ENC.DLL
(2) BeLight with AC3ENC.DLL
There is also some older software that I used, but it's no longer made. I have the old Sonic Found SoftEncode, made by the people that made SoundForge
. Sony now owns SoundForge
and Vegas and other SF products, but SoftEncode is discontinued. You may be able to find it used on eBay
The other options tend to be AC3 conversion at authoring. Software like Sonic DVDit! PE and Ulead DVD Workshop 2, even Tsunami DVD Author, all have built-in AC3 encoding available. Many home uses use this, they don't encode to AC3 beforehand, and that's fine.
Professionals tend to use AC3 encoders that come with their pro authoring software. Sonic Scenarist and Apple DVD Studio Pro both come with professional AC3 encoding software. Many pros even use AC3 encoding hardware.
Let me know what route tickles your fancy, and I'll try to give you more detailed information on it.
I currently use BeSweet. I have no problems. Although it can be a bit more difficult than some of the other options.