If you use Itunes make sure you use one of the lossless formats like WAV, AIFF, FLAC, Apple Lossless. MP3 and some of the others are very poor quality. I have CDs, SACDs, and DVD-Audio, so far i have only converted CDs and I am working my way through very slowly.
http://lifehacker.com/5927052/whats-...e-should-i-use