Google Play Music – Find Songs Rated ‘Thumbs Up’

No, there is no limit, but Albums may end up split or joined based on information in the Track Info and Album Info.

Here is an example of multiple albums merged into one: If you note, there are 52 tracks in the album and there are also a number of duplicate track numbers, as well as multiple artists.

This can be further explained by looking at the Album Info: Here we see some key elements empty:

• Artist
• Album Artist
• Tracks

Though these are not required they can help group the tracks. Which, if we look at a few of the Track Info panels:

We see the missing info cause a common pattern linking separate albums into one. Adding an Album Artists can quickly change my issue, but since you are looking to merge albums/collections removing elements from the track info (that would help ensure proper grouping of tracks) should give you the results you are looking for.

But I'd recommend using the "Playlist" feature, that Google provides, to get better results for groups and minimize future confusions should you decide to share your tracks.

ChrisF's answer is mostly correct, but I think it has a subtle error:

If you change the name of the file Google Music will upload a new copy of the file as, as far as Google is concerned, it's a new file.

I don't think this is entirely true. When the Music Manager scans a file, it generates a hash of it (you can find this in the Music Manager local database - it's called the "client id"). Importantly, the hash attempts to depend only on the track's audio, not on filename or metadata tags (further details here).

This means that if you change the tags or filename, the Music Manager should recognize it as a change to an existing file and not create a duplicate.

That said, there are two wrinkles to their solution:

• the Music Manager doesn't recognize some ways of storing album art (eg if art is stored in a local file, but not in the file tags)
• the hash isn't entirely dependent on the audio, since tag stripping is done on a best-effort basis. You can see this effect by adding more obscure tags (eg adding an APE tag on the end of the file will result in a different hash, while an id3 tag won't).