Need help with AC3 to AAC

[Sagekilla]

Hi all, I'm looking to transcode my 5.1 AC3 audio files to 5.1 AAC. I'm sure this is a pretty common question around here, but the last time I tried it I got very poor results. Can anyone point me towards a guide, thread, or tell me what's a good quality method of transcoding from 5.1 AC3 to 5.1 AAC?

Thanks!

[nautilus7]

You can use eac3to (output to stdout) and nero aac encoder.

eac3to your_input_file.ac3 stdout.wav [-libav] | neroaacenc -ignorelength -if - -of your_output_file.mp4

Note that the -libav option in the eac3to is needed only if you don't have nero 7 & nero hd dvd/blu-ray plug-in. Of course you can add any parameters you want in the aac encoding part of the above command, but the ignorelength is obligatory.