Convert 320kps (or any kps) to iTunes

If I have a 320 kps CD and I import it to iTunes at 320 kps will the sound degrade further? Same for 256 AAC to 256 AAC etc.

 

Depends

If the CD has the MP3s as data files there will be no more degradation.

If the CD has music files then there will be further degradation from the decoding/re-encoding process, unless you import as lossless.

 

Perfect answer on first try. Thanks so much.

 

I should add that if the mp3s are data files you have to add the files to the iTunes library, not import the CD

 

Just to continue, theoretically, a music file converted from 320kps to 256 AAC would not be the same as a lossless to 256 AAC because we're starting with less info to begin with. Right?

 

Correct. Lossy to lossy will always be worse than CD or FLAC to the same bitrate MP3/AAC. Whether you can tell the difference or not is a different story. I often transcode my 320kbs files, usually supplied with the vinyl via download card, to variable bit rate AAC. Why? Because the encoders work their best at variable bit rate to maintain quality and limit file size. 320kbs are way too big in my opinion for portable listening, and I can usually shave off sever MB's of data without any artifacts that I can hear. However, if I ever stumble upon the CD or FLAC files, I do re-rip from the lossless audio.

So far, going from higher bit rate to lower has seen pretty good results for me. But the other way around is not recommended. Going from 128kbs to variable bit rate, or 256 AAC in your case, would yield higher bit rates with no boost in quality. I also don't think I'd take something that's already VBR and make it a lower VBR.

 

Thanks so much. It was a difficult question to word but that was a great answer. I have CD-Rs that people have made for me and I've been using 256aac to import them to iTunes. I guess that's the safest bet considering I don't know what the CD-R kps is. Thanks again