Pete0 wrote:
Apple Support, citing the "About" for Mastered for iTunes, contradicts your assessment:
"No. It is not possible to upgrade your past purchases to the Mastered for iTunes version if one is available. If a previously purchased song or album is now being offered as Mastered for iTunes, you will need to repurchase the song or album if you wish to obtain the improved audio."
Here's the link to the "About": http://support.apple.com/kb/HT5156
Bummer.
I suspect they would say the same if you asked whether your old version of an album could upgrade to a remastered version, but we know from experience that it does actually match to some tracks, at least.
There is plenty we don't know about this though. If they keep an old version of the albums in iTunes then our it is most likely that those will be matched. However, if older versions are removed from the store (as often happens with remasters) then our experience suggests that some of the remastered tracks will match.
Another thing we don't know about is what happens when the version of a song that is matched is removed from the store. I imagine that the version you were originally matched with will stay in your cloud, but it isn't clear. What about if we remove the tracks from our libraries, wait for the cache to clear, and then reintroduce them. I imagine that it will then forget about the original match and may then match with the new version (waveform permitting).
Basically, we don't know, but I wouldn't rely on what Apple Support say.
One thing I suppose that we do know from experience is that, even if some tracks match to a mastered for iTunes version, it is unlikely that a complete lbum will. This can make for a worse listening experience than if it just stuck with the 30 year old masters.