Yeah, that's going to need some re-encoding, and the process of doing takes a LONG time, especially if you've got an older computer (a 720p film took about... 36 hours on my 2.4 GHz Pentium 4).
I really wouldn't recommend it unless you ABSOLUTELY wanted DTS audio. Again, can you tell the difference between DTS and AC3?
Answer that, first, before we start on the re-encoding process.
ill leave it then i cant really tell the difference i have a amd 3.8 running at a 2.4ghz so the same as yours.i have the gigaworks g500 speakers and the dts 100 decoder.does both dolby digital and dts.but not hd formats put plays fine when using the blue ray movie i made by spliting it and the dts kp is 1500.so is this hd dts or not.if i just use ac3 audio by using eac3togui is there any settings in this program to make the ac3 sound better thanku so much u have been great help.
You know, I can't be sure whether 1,500 kbps is around HD or not. I would think so, but I could be wrong...
Anyway, it doesn't seem like there's an option to go beyond 640 kbps with ac3 audio. I don't know much about using eac3to or about audio conversion in general, so I'm not of much help here.
I think 640 kbps is as far as you're gonna get with ac3 unless someone else comes in and informs you.
As far as making it sound better, though, you could try fiddling around with some of the force filters and stuff. But yeah, the little itty-bitties of codec settings and stuff is lost on me. I just try things out and see what works best for me.
DTS @ 1536kb/s is not HD, its the hightest bitrate of DTSsurround sound that will pass through optical. Typically it's the core of DTS HD-MA or Hi-Res which requires HDMI as a transporter.
When using eac3to and the GUI you are working with... Ideally for the best output you want to chose AC3 @ 640kb/s and use "default" as the force filter. Since you are converting DTS to AC3 the best way would be to have an Arcsoft product installed to decode the DTS stream (it's the prefered, or best decoder at the moment), if you do not have Arcsoft the it will automatially default to eith Sonic (another commercial media package) or Libav... which is bundled with eac3to.
If all else fails select Libav as the Force Filter. Also, the first time you use eac3to with eac3toGUI you will need to configure the eac3to path in the settings menu.
EDIT: FYI, eac3to uses Aften to encode to AC3... which is a good encoder. So rest assured you will get a good AC3 track, provided the source is also good (not damaged or poorly encoded).
