MeGui vs Foobar2K AAC encoding

[Hvidgaard]

Hi,

I was converting and 5.1 audiotrack to stereo AAC using Foobar2K and NeroAacEnc, but decided to give megui a shot, but the file outputed by MeGui is 128mb vs only 88mb with FB2K. I Used aac-lc and vbr q=0.40 for both and obviously the same encoder - so the only thing I can come to is that they downmix 5.1 to stereo differently? Is that correct? and does someone have any experience with this (in terms of which is better)?

[Hvidgaard]

hmm, found out the MeGui encode is a full 21 sec shorter for a 118min track... Guess MeGui is not usable to encode audio :(

[Hvidgaard]

perhaps this should be moved to the audio forum?

[foxyshadis]

Not a bad idea.

Did you choose downmix to dolby, or downmix to stereo, in the aac config? Dolby modes will use a higher bitrate for a given quality level, because they pack the surround channels into the upper frequencies of the stereo mix.

Also, what was the method used to acquire audio? Directshow is quite a bit more prone to errors like the 21s short than nicaudio, the default.

[Hvidgaard]

Not a bad idea.

Did you choose downmix to dolby, or downmix to stereo, in the aac config? Dolby modes will use a higher bitrate for a given quality level, because they pack the surround channels into the upper frequencies of the stereo mix.

Also, what was the method used to acquire audio? Directshow is quite a bit more prone to errors like the 21s short than nicaudio, the default.
I used the buildin option to downmix to stereo in both cases. I don't know how the audio is feed to MeGui, but I guess it is DS so could be the problem.