I love Planetarian. As someone who enjoys compact and self contained experiences, I think it’s a great example of how even a short story can have a big impact.
Planetarian’s soundtrack was really compact, too. Of the ten songs that appeared in the game, four of them are variations on “Hoshi Meguri no Uta” [Song of Circling Stars] (Yumemi’s theme). I really wish we saw more variations on the heroines themes in the other games, but I think it’s used to great effect here because it makes the short game feel very tight and cohesive. An interesting note that I picked up on was that the first two versions of that song you hear are the “~Honky Tonk~” and “~Metronome~” versions which have a very snappy staccato beat, that creates this clocklike “tick tock” sensation. I think this really reinforces Yumemi’s robotic nature, and sets up a beautiful contrast with the “~Winter’s Tale~” and MELL’s vocal rendition which are much smoother, more lyrical, and really reinforce Yumemi’s inherent humanity.
“Ame to Robot” [Rain and Robot] is, fittingly, the song that plays when Yumemi’s standing out in the rain. I have mixed feelings on this song. The melody and drums are gratingly MIDI, moreso than most of Key’s songs, but the steady accompaniment conjures up such a strong image of rain drops pattering steadily on the roof that I cannot help but feel like that juxtaposition is exactly what the composer was looking for.
“Hoshi no Sekai” [World of Stars] and “Itsukushimi Fukaki” [Deep Affection] are also fantastic. The former song is the music-box opening song, and the latter takes that same melody and layers a few more layers under it. Once again, the Planetarian soundtrack is incredibly compact, and it was great to hear the opening sneak back in later.
I’m not sure why, but I get the sense that “Gentle Jena” was the song from Planetarian that Key decided should be the iconic one. An arrangement of it showed up on Ma-Na, and to date I believe it’s the most widely remixed of the VN’s songs among fans. It’s a nice song, and I think it’s quiet optimism does represent the story well, though I do wish more of this novel’s songs would get some love!
I don’t have much to say about “Human Warrior.” It’s definitely different from the rest of the soundtrack, and it’s definitely appropriate where it’s used. It doesn’t stand out to me, but it does its job well.
That, of course, brings us to “Mattaki Hito” [Perfect Human] A.K.A. the song we all cried to when Yumemi dies. The song has a whole hell of a lot of gravitas, and I think the name really drives home the point that we’re supposed to see Yumemi as a person, not a robot. It reminds me vaguely of church music, with the ethereal chords sounding something like an organ reverberating in a massive hall.
Overall, while there isn’t a lot of music in Planetarian, every piece has a job to do and does it well. I think this is helped along by how focused the story is. For other VN’s, there are a wider range of events that might need to use the same music because the moods are similar. But in Planetarian, we only have one character to interact with, which means we can have more variations on her leitmotif, and the other songs only show up a limited number of times, so they don’t have to be stretched to fill disparate purposes.
On a side note, if you enjoyed Planetarian, check out Digital: A Love Story, which has some similar themes and was partially inspired by Planetarian, according to the author.