Q: Just read your response to reader’s question regarding iTunes Match. It clarified a few concerns I had. I do have an additional question, however. Assuming iTunes scans my entire music library, and assuming I delete my library to preserve HD space, when I later download some tracks back onto my HD, will it download in the original form in which it was matched/uploaded? In other words, I’m very particular how my music is tagged (i.e. I tag my albums differently than the iTunes has its albums tagged), so when I download a particular album back onto my HD, will it download that
particular album containing my tags, or will it just download with iTunes’ tags?
A: While you should be fine in terms of your custom track metadata and tags, it’s important to note that you won’t likely get all of your tracks back in their exact original form.
In order to avoid having to store millions of redundant copies of tracks on Apple’s servers, iTunes Match takes advantage of the very large catalog of music that is already available on the iTunes Store. When you setup iTunes Match, the iTunes application goes through your library and tries to match as much of your library as it can to music that Apple already has available. If a track can be matched, it’s simply “linked” to the version that is normally sold on the iTunes Store; only those tracks that cannot be matched to something already available on iTunes are uploaded directly to Apple’s servers.
Despite this, however, iTunes maintains a virtual copy of your iTunes library database in the cloud as part of the iTunes Match service. Much like the iTunes library database on your Mac or PC, the cloud-based iTunes Match database contains all of your track metadata such as name, artist, album, genre, artwork, and even play counts, last played dates, and playlists. When you download an iTunes Match track to any iTunes library, even your original one, the metadata is filled in based on the information you provide. Note that this applies even for tracks purchased from the iTunes Store—if you’ve customized the metadata for those tracks, that’s what will appear in your iTunes libraries and other devices connected to iTunes Match.
In the case of “Matched” tracks, if you delete the original track from your iTunes library and re-download it from the cloud, you will get the same 256kbps AAC version being sold on the iTunes Store, but the track will have your customized metadata applied to it. For most users this is effectively an upgrade to a higher quality version, but if your library already consists of higher bit-rate tracks, you’ll definitely want to preserve those elsewhere before deleting them.
On the other hand, this won’t be an issue in the case of “Purchased” or “Uploaded” tracks. For Purchased tracks, what you have in your library should already be exactly the same as what’s on the iTunes Store since that’s where you got it from in the first place. For “Uploaded” tracks, iTunes has in fact uploaded an exact copy of what was in your library to Apple’s servers, since it couldn’t find a copy to match it to, so when you download it into iTunes, you actually are getting that exact copy right back.