AacMachine

AacMachine v0.4x is a front-end that automates the AAC encoding process. It uses BeSplit in order to cut the AC3 source into small pieces, BeSweet in order to decode the AC3 into a normalized WAV file, then AacEnc to encode this WAV file to AAC, and then again BeSweet to merge the small pieces into one long AAC track. The 0.4x builds focus on 5.1 AC3 to 2. 0AAC & 5.1AAC processing.

Once you've started AacMachine, configure the location of BeSweet.exe, BeSplit.exe, AacEnc.exe and the input file. You would also need to specify a temporary path for all the splitted AC3 files. (Default is C:\).
The output file will be automatically set to have the same name as the input, with .aac extension of course.

Then configure the downmix options. These are essentially the same settings as in the Azid/BeSweet GUI. All you have to set is set LFE to LR Channels to -3db and leave the rest unchecked.

Then the overall settings:

Channels mode sets the resulting output format. Surround2 means you get a Dolby Pro Logic II optimized downmix, surround means you get a Dolby Surround encoded file which is the default. Stereo would only give you a stereo file whereas 5.1 would result in a 6 channel AAC. Keep in mind that you need a soundcard having an analogue 5.1 output to make full use of a 6ch AAC.

Set Dynamic compression to normal to get about the same dynamic range as when you play the AC3 from DVD on your PC/TV. note that BeSweet can also compress the dynamic-range of MP2/MP3/WAV files using its internal routines. Therefore the 'Dynamic Compression' switch is always relevant.

Also check Auto Find Maximum Gain so that you won't have to turn up the volume each time you watch the movie.

Last but not least let's configure the AAC output.

Select VBR Preset - then the desired type. Using the Internet preset will result in a bitrate of about 100kbit/s, Normal is around 130kbit/s, Extreme is around 210kbit/s, Archive 270kbit/s and Ultra 310kbit/s. The higher the bitrate the higher the frequency cutoff. Tape and Radio are definitely below our quality requirements.

Use ADIF header would produce an ADIF AAC stream instead of the default ADTS AAC stream. ADIF streams are supported by portable AAC players like Phillips' Expanium.

If you absolutely need downsampling you can also check Set Sampling Rate to so that SSRC will be invoked to downsample the audio.

Once you're all set press the "Give me AAC!" button to start the conversion. AacMachine will start the transcoding process and printing status updates like "Splitting source file", "decoding part 1", "encoding part 1", etc.
If you get a runtime error you most likely haven't properly configured the path to BeSweet.exe or you need to download the latest release of msvbvm60.dll. Don't forget to check Output to Logfile as it will help you in case you're having any problems (basically you can't expect any help in the forum if you can't supply that file.. it helps us determine what could've gone wrong).