Overview
Captain Fantastic (Original Score) is the first soundtrack released to accompany the 2016 film Captain Fantastic directed by Matt Ross, featuring the film's original music composed by Alex Somers, known for his collaborations with Sigur Rós frontman Jónsi, under the name Jónsi & Alex; it also marked Somers' film scoring debut. The album was released by Lakeshore Records on July 8, 2016, alongside the film, with a vinyl edition published by Invada Records on July 29. The second soundtrack, entitled Captain Fantastic (Original Motion Picture Soundtrack) consisted the diegetic music featured in the film, released a week later, on July 15.
Development
Ross liked the musical works of Sigur Rós and also Somers' collaborative album with Jónsi called Riceboy Sleeps (2009). He and the film's editor, Joseph Krings used much of the music from the album as temp tracks for the rough cutting and liked the dreamy atmosphere. He then sent the script to Somers, who was fascinated by the idea of "leaving society altogether and make the move out into the nature" agreeing to be part of the film.
Somers did not rely on an ambient music and instead the way he built with. Some of the challenges he felt were finding ways to have the music reflect the character's growth through out the film, where "the family leaves their home in the forest and enters society and that major change needed to be reflected in the music somehow" which was tricky to show them. He and Ross wanted the music to strongly underpin the story and the characters, and did not want the adventurous feeling to play too much. Therefore, the music "embodies the spirit of the character’s wildness and the isolation that comes with living in the middle of a forest".
Somers mostly developed the sounds by the old-fashioned way, recording to the finished film he was sent. He had a lot of time scoring the film as the filming was completed long back, and had no deadline pressure, so that he could record, re-record and experiment those tracks. The piece he wrote for the very first scene of the film, had to be deleted for the film, as he felt that the nature sounds being apt for the scene.
From Wikipedia (CC BY-SA 4.0).