In the description for Ar no Surge: Ode to an Unborn Star, it talks about how song and music are used as magic and for character development.
AR Nosurge Ode To An Unborn Star PS3 is a Fantasy, Sci-fi, '7 Dimension' RPG, that takes place in a world where music and song can create magic.
Ar Nosurge: Ode to an Unborn Star has a unique character development system that focuses more on the bonds/ relationships between the main characters than their success in missions and battles, as the player's party grows stronger if the characters have a closer relationship.
Now, this sounds much like the Ar Tonelico series, which talks about how music is used as magic and how you need to develop the character's relationships with one another to develop their strength. Also, both games were developed by Gust.
This makes me wondering: Are the 2 games are related story-wise? If they are, when does Ar no Surge: Ode to an Unborn Star occur in relation to Ar Tonelico?