Surfing online, often see people asking questions like this: "Does anyone know how to convert 5.1 AAC to AC3? If so, what software do I need and encoding/conversion settings. Thanks in advance for any help." As a matter of fact, this is a normal question, because some of our usually used multimedia devices can decode or read audio codec selectively only, we have to do format conversion to meet their requirements. For example, some theatre amplifier can only decode AC3 5.1 format, while Apple TV can only deal with AAC audio, or whatever. In this post, I’d like to document a easiest way to convert AAC 5.1 to AC3 5.1, in the near future, if I have enough spare time, I’d like to talk more about how to convert AC3 to AAC, that may be in my another post.
To convert AAC 5.1 to AC3 5.1, you just need Pavtube Video Converter
only. This program is capable of reading a wide range of video and audio formats, including videos from DVs or camcorders (JVC, Panasonic, Cannon, Sony, etc.), TiVo (*.tivo), DVDs (*.vob), Blu-ray (*.m2ts,), YouTube (*.flv, *.f4v), and many other videos in common media formats, like mp4, avi, mkv, ts, tp, evo, aac,dts and so on. The detailed process is as below:
Step 1: Click "Add" button to load your video files
Step 2: Select output format and specify save path
Click the pull down menu of "Format" to select your needed format, here I choose "MKV HD Video (*.mkv) for instance. Click the folder icon at the end of "Output" to decide where to locate the output files.
Step 3: Click "Settings" icon to specify AC3 5.1.
Once click "Settings" button, a "Profile" window will pop up as above. Now you should select ac3 as audio codec, and select 5.1 as audio channel. By the way, you’d better adjust audio bit rate at 448K to match the effect of 5.1 channels to full extent. All needed settings are completely showing in the above interface, you just need follow them, and this will lead you to get an AC3 5.1 surround sound successfully.
Step 4: Click "Convert" button to start conversion
As long as conversion is finished, you can click "Open" button to find out the output files with the converted AC3 5.1 channels.
Well, hope this helps.
For more: http://www.pavtube.com/video_converter/