Hi SpuD. For music I'd stick with Itunes, it converts to AAC mp4 which will give you the same quality of an mp3 but at a lower kbps. For example a mp4 96kbps sounds as good as an mp3 192 kbps. A mp4 at 192 sounds pretty close to the original cd track. However, it also depends on what you're using to listen to your music. A mp3 player with some earbuds might sound pretty good rockin a 192 kbps mp3, but plug it into a stereo receiver with some high end speakers, turn it up half way and the audio will sound like crap, your bass will distort, and the highs won't sound as crisp. Or you could try out Gordian Knot and re encode all your audio on a more custom level, or just plain mux the audio and keep the original quality. I like to re encode my videos with ogg vorbis 5.1 surrond at 192 kbs. The audio sounds really good on my bose acoustic 3 headphones. Unfortunatly I can't do any real testing till I get home from deployment.
Kbps means measured in kilo-bits-per-second, and VBR is Variable bitrate, a term used in telecommunications and computing that relates to the bitrate used in sound or video encoding. As opposed to constant bitrate (CBR), VBR files vary the amount of output data per time segment. VBR allows a higher bitrate (and therefore more storage space) to be allocated to the more complex segments of media files while less space is allocated to less complex segments. The average of these rates can be calculated to produce an average bitrate for the file.
Hope this is helpful.
Edited by vittorio, 23 November 2009 - 06:08 PM.