QUOTE(analogy @ Oct 29 2004, 01:54 PM)
For Multi-CD albums I use a "disc" tag to mark which disc in the album a track is from.
I put the disc number in as part of the album name, like "album name (disc n)". This way, if I am using a player that doesn't support APE tags on MP3s, it will still display it, since the "disc" field is not part of the ID3 standard as far as I remember. Then for consistency, I follow this convention even for other formats that will support a "disc" tag, e.g., Ogg Vorbis tags or APE tags. As an aside, my filename convention for various artists albums is like:
album (disc n) - tracknumber - artist - titleor
album artist - album (disc n) - tracknumber - artist - title (if the album artist is the same for all)
so that they will sort properly in file listings. I also keep all the files for all the discs in one big folder, not separate folders for each disc, so I can see them all at the same time.
QUOTE
If the CDs are separate works that happened to be bundled together, I'll replaygain them separately.
In this particular case, each CD is an individual set (hour long DJ mix), so I guess then it makes more sense to replaygain them separately, since they didn't really promote it as a 5 hour long set, or two 2.5 hour sets, but six 1 hour (or so) sets.