Q: Since signing up for iTunes Match, I have a lot of albums that have a mix of matched and uploaded tracks. I don’t understand how iTunes can match only two or three tracks from an album and force me to upload the rest. Shouldn’t the Match feature do complete albums? Also, when I’ve looked for some of these albums on the store, I can’t find them, yet iTunes Match definitely does match at least some of the tracks. Any idea what’s going on here?
A: This may seem a bit confusing when you look at it from an album perspective, but in most cases iTunes Match is actually working exactly as designed.
Two important points that may help to explain what’s happening here: Firstly, iTunes Match works on a per-track basis, not a per-album basis. Secondly, iTunes Match preserves whatever track information (metadata) is assigned to tracks in your own library.
iTunes Match identifies matches between tracks in your library and tracks on the iTunes Store independently of album information. Since it’s not uncommon for many artists to include an identical track on more than one album, iTunes Match will often be able to match up a track regardless of whether the album that you have in your library is actually available on the store.
However, since iTunes Match uses your tag information rather than overwriting it with its own, the “matched” track will still be listed under the album title from your library, even though it’s technically being matched up from a completely different album. The good news, however, is that the matching algorithm appears to be accurate enough that tracks are only matched if they’re actually the same song, as opposed to variations or remixes, so the resulting tracks should be identical to what’s already in your library.
Of course, it’s pretty unlikely that all of the tracks from a given album are available on other albums, so those tracks that can’t be matched to the iTunes Store are simply uploaded, creating the situation you see with a mix of both matched and uploaded tracks in the same album.
Note that in some cases this can even happen with albums that appear to be the same in your iTunes library and on the iTunes Store. Sometimes different album releases may include or exclude certain tracks, or provide different versions of those tracks, particularly in the case of releases in different countries. The same idea still applies, however; iTunes is matching what it can on a track-by-track basis, and uploading whatever can’t be specifically matched.