Recent experiences with iTunes Music Store along with a growing knowledge of how audio files are put together have inspired me to make this guide, or more subtly this warning. As it stands you can buy iTunes music for 1.30 USD and it will be free of DRM. That sounds good right? The DRM songs cost 99 cents.... What then is the warning? It's this... buy the CD, always buy the CD. Forget iTunes, forget Rhapsody (they won't let you cancel except over the phone, and then they harass you). Here's a few reasons for my thinking: 1. It seems that audio files in general are not self-correcting, or rather they do not know whether they are accurate copies of the original. What I mean to say is there are more then 1 type of AAC file (which iTunes sells), they actually have 3! iTunes Music Store sells 128 AAC files encoded with Low Complexity or LC. The newest standards are AAC+v1 & AAC+v2, these are High Efficiency or HE. These would be the preferrable audio files for any of your songs, but iTunes uses LC! Ahemm.... Let me continue, did you know iTunes has no self checking mechanism in place to make certain the song you download is a perfect match to the ones on their servers? That means if you are somehow missing 3 bits off it somewhere you'll never know, not that it would make a difference but still :C~ Even more annoying is that mp3's and it seems mp4's are made so that if they are damaged they'll still be able to play! That's right, instead of developing systems for these to verify they're ok these companies etc. have designed systems that ignore errors! Hahaha.... The best way to catalog your music collection, and anything in general, would be to get a CRC / MD5 / ETC catalog utility, one that can keep a record of the files exact configuration at the time you've bought it. This way down the line you can compare the record to your file as it currently is, but alas this is the only way! Normally one might expect the audio file to keep it's own internal record just so nothing ever corrupted or distorted its sound, what we see however is that these audio files have no such system. I can quite possibly take your mp3, open a hex editor, slice and dice it, and it would still play SEEMINGLY ok. What a joke ehh? So steer clear of current systems for downloading music, that is if you'd like to keep it for years to come. Use a utility to catalog your files CRC / MD5 / ETC. and maintain this record. If you do this properly you'll always know if something is wrong, a file changed, and so on.. My other advice is that you not encode your CD's into a lossy format like AAC, MP3, etc. Instead use something like Exact Audio Copy EAC and burn your tracks into FLAC or APE files, these are complete copies of the CD not lossy. Anyways those are my answers, good luck friends and never forget collecting music is fine, but when you are 6 years down the line and find corrupt music or such nonsense, or that your codec is no longer supported, remember it's always better to have a CD.
