A while ago (actually, almost two years ago <g>), Chinese Sausage wrote the below answer; it’s on my research list to see if I can stream out my audio library:
Re: Best format to encode into?
« Reply #2 on: 2011-08-14, 14:50:18 »
When space drive IS a concern, then ogg (aoTuV version) is the best format quality-wise (to these ears), as it is more true to the original music source, and it leaves less noticeable noise artifacts than the other encoders. However, aac is almost just as good and also more compatible with mobile phones, iPod’s and other external players, so it is probably a better choice if you want to share your music files with anybody who is not computer savvy. The main thing I do not like about aac (at least HE-AAC) is that it does not support gapless playback, which is particularly annoying if you listen to live albums, or other music which has continuous playback.
At 64kbps though, there is none better than ogg aoTuV. Here is a link to the latest version, in case you want it.
Just replace the ogg.dll and vorbis.dll files to the existing ones in your encoding program (I use MediaMonkey to encode files to ogg).Hope this helps!
--jeroen
via: Best format to encode into?.
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