I am going to do a bit of copy/paste of posts I did in the Plex Pass only forums:
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1.“Various Artists” is the usual choice for ‘Sampler’ style albums. There may be exceptions for ‘collaboration’ albums which are credited to all participating artists on the album cover.
2. use the title of the single as it appears on the cover. You can augment that information with (CDM) or (single) or (Maxi) or (EP) as it fits. If it is a genuine release, Gracenote should have no problem identifying it.
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It is recommended to do it like your version “after conversion”.
You can usually get by with the version before conversion if your metatags are well maintained.
I’d recommend to use a different delimiter character after the track number. It is easier to distinguish for automated renaming and tagging software which part of the file name is which information. I use dots.
If you have a lot of albums, it is no problem to insert an additional level of ‘artist’ folders:
If you are just starting with plex and want to reorganize your files anyway, I recommend the following approach
Music /
Artist /
Albumartist - Albumtitle /
1. trackartist - tracktitle.mp3
2. trackartist - tracktitle.mp3
...
and for a multi-disc album:
Music /
Artist /
Albumartist - Albumtitle /
Disc 1 /
1. trackartist - tracktitle.mp3
2. trackartist - tracktitle.mp3
...
Disc 2 /
1. trackartist - tracktitle.mp3
2. trackartist - tracktitle.mp3
...
do note the distinction between Albumartist and Trackartist.
There are separate metatags for these. You need to fill both.
This then provides a means to deal with sampler albums:
The typical sampler simply uses as Albumartist Various Artists
And that is what you should use too, since Plex treats ‘Various Artists’ a little different. (the standard album sorting mechanism is by release year, descending whereas for Various Artists it is alphabetically, ascending)
If you are on Windows, I recommend you to use mp3tag. It can read and write metatags for all the common music fileformats + mp4/m4v
It also supports deriving metatags from folder/filenames and vice versa, which is excellent for bringing your collection into shape.