Time to clear some stuff up...
Hoshiyomi - Ar tonelico hymmnos concert Side Ao
Misha's songs, and some BGMs.
Tsukikanade - Ar tonelico hymmnos concert Side Kurenai
Orica's songs, and some BGMs.
Those 2 above and the OST makes for all the music you will find in the game, except Claire's song I think...
There are many other Drama CDs with new songs, but they are linked to the drama dialouge.
Claire's song(s) are on Hoshiyomi (performed by Yuuko Ishibashi). But she does a little extra singing on her own album, the Hymmnos musical (there's a second one coming out for Spica as well).
Except for the four drama CDs released by Frontier Works (Side Orica, Side Misha, Side Shurelia, and Side Extra), all of the Ar tonelico soundtracks are on this site, they've been reviewed for ages. Depressing that people had to ask questions about them on this forum...and Silverwolf, since you said you actually listen to the drama albums, I'd love to see some soundtrack reviews for the AT drama CDs! ^^
I actually recommend Ar-Tonelico, Hymnos Concert Side Blue (Ao) ~ Hoshiyomi (Reading the Stars) and Ar-Tonelico, Hymnos Concert Side Crimson (Kurenai) ~ Tsukikanade (Playing the Moon).
The tracks are vastly remastered and improved versions from the original pieces found in the game, on the original soundtrack. Definitely my favorite out of any tribal chanting albums I have.
What's with the "on the original soundtrack" statement? Outside of the opening and ending, the songs on the Hymmnos Concerts are all exclusive and NOT found on the OSTs (Japanese or US). And, they ported over the exact versions of Expressive Hill ("Singing Hill" according to NISA) and Phantasmagoria, so.......don't know what that part was. But Bernhardt is 100% correct that the in-game versions of the songs are ... umm ... lacking, compared to what's on the albums. They just sound like REALLY rough cuts in-game.
I didn't realize there were so many endings in the game, like 7 or 8. I'm only planning on playing this game once, but it's nice that it has a high replayabilty for those that like doing that.
One playthrough in the game can net you half the endings on the way. The real "split" is:
Partway through Phase 1 of the game, you choose who to install the Purger crystal into. This basically determines which girl you officially "go for," though you are free to finish the Cosmospheres of all girls. I chose Aurica. Choosing Misha alter's the game's path slightly, and gives you "Misha" endings instead of "Aurica" endings.
The variations in the endings are so tiny that it's hardly worth mentioning. Getting the "highest" level ending unlocks a cute costume to look at in the "Extras" menu...that's about it.
You can choose to end the game at Phase 2, which you...really shouldn't do, that's like only halfway-beating the game. Phase 3 allows for a bad ending, a good ending with Aurica/Misha, or a Shurelia ending. Thus, regardless of you choosing Misha or Aurica, you can pick up all of these endings on the way.