“It was a bit of an experiment,” the two-time Oscar nominee concedes. “I would write ideas and John [director Krasinski] would try them against scenes.” He visited the set in New York, and they frequently debated what could better left in silence and what might need musical support.
Beltrami’s brainstorm: “This idea that they’ve been isolated from any real sound source for a long time, so even their idea of music might be somewhat faded,” led to a slight detuning of a piano’s black keys “so that it becomes a little bit off.”
He also wrote a warm family theme, and music for the monsters (which he didn’t see until about a week before the final recording session): “a rising pulse idea, basically increasing tension that keeps building, almost like an emergency beacon.”
Beltrami recorded a fairly small ensemble of about 30 musicians and then performed extensive manipulation and processing “so that we could create sounds that were semi-orchestral and semi-electronic.”