AC3 or AAC 5.1 for Media Server?

[aguy]

Hi there.

I am in the process of backing up all my DVD's to a media server for access across my network to HTPC.

I am planning on using x264 with crf =18 for the video. I have been researching about the audio side of things.

I am down to a choice between keeping AC3 stream or transcoding to AAC5.1 with neroaacenc. I am wondering what other people do and what typical bitrates people aim for if they do transcode (or q values for nero multichannel aac).

To give you an idea of my acceptable quality for audio I encode all my CD's with LAME at preset standard (VBR about 200kps).

Thanks

[Favorito]

If your acceptable quality for stereo 2-channel audio REALLY is ~200 kbps VBR LAME, than don't even think about encoding 6-channel AC3 448 kbps(which is already compressed)to anything else. However,you may do some listening tests(ABX)to find out if you really need such a high bitrate as even 96-128 kbps with modern audio codecs give most people hard time to decide if it is original or not.

[Favorito]

Now,in 5.1 audio situation is this:2 sets of paired channels(L,R and SL,SR)+center channel(mono)+LFE(bass). So if you want to get 5.1 AAC audio with quality comparable to lets say 128 kbps stereo:128*2+64+5(as LFE requires very little)= ~320 kbps. That should sound 99% transparent to original. 256 kbps is also very good. You can use 160-192 HE-AAC to. HE is not for audiophile,but still good.