Q: I have recently bought a subscription to iTunes Match. I would like to know if my music in the cloud can be shared with my wife? She has an iPad and iPhone with a separate name and password for iTunes.
A: iTunes Match works on a per-account basis, and there is no way to share iTunes Match libraries between separate iTunes Store accounts.
However, you can definitely share the same iTunes Store account between multiple iOS devices in your household. Apple allows up to 10 devices to be registered under a given iTunes Match subscription, up to five of which can be computers running iTunes. This should provide enough device registrations for even the most connected iTunes families to share a single iTunes Match library.
To make this work, you will need to both log in using the same iTunes Store Apple ID and password—whichever one you’ve setup for iTunes Match. If your wife maintains a separate iTunes library on her own computer, she can simply add that computer to iTunes Match using the same Apple ID and password that you have already purchased your subscription under. This will add any music from the second computer that isn’t already in the iTunes Match library—either matching it or uploading it as required, in much the same way as when you originally signed up on your computer. The final result will be a cloud-based library that is an aggregate of content from both of your individual libraries.
If you wife has purchased music under her own iTunes Store account, it won’t automatically appear in the purchase history for your account, however any tracks purchased after 2009 should be unprotected and can simply be matched or uploaded in the same manner as any track added from other sources such as your own CDs.
The only catch will be dealing with protected tracks—most tracks purchased before 2009 and all tracks purchased before 2007, when Apple first introduced iTunes Plus.
In this case, as long as your wife’s computer is authorized for the account that was originally used to purchase those items—which it should be if she can actually play them—then the iTunes Match process will try to match these tracks and add them to the iCloud library. If they can be matched, they will be available on other devices as unprotected, 256kbps AAC files; if not, they will be uploaded as-is, including the DRM protection, and you will only be able to play them back on devices that are also authorized for that iTunes Store account.
For sharing an iTunes Match library going forward, it is best if all music purchases from iTunes are made under the same iTunes Store account as the one used for iTunes Match. This will ensure that the items are automatically available in your library as “Purchased” items rather than having to be matched up. This will also make things a lot easier as switching iTunes Store accounts on a given iOS devices or computer disables iTunes Match, requiring you to manually re-enable it once you switch back to the proper iTunes Match account.
Keep in mind that as with syncing two devices directly to the same iTunes library, sharing an iTunes Match library means that you will also be sharing all of your playlists, tagging information, and most importantly data such as ratings and play counts.