The musical landscape for Pixar’s “Soul” was one of two worlds. “The Late Show With Stephen Colbert” resident band frontman Jon Batiste used a jazz-filled, hectic musical palette to reflect New York City and the world of Joe Gardner, a middle-school band teacher who yearns to be a jazz pianist in the Pete Docter-directed animated feature.

A prepared piano — an instrument with its sound temporarily altered — helped Batiste find his way into the sound of the celestial world that Joe finds himself in after plunging down a manhole.

The world is “the Great Before.” This is where composers Trent Reznor and Atticus Ross stepped in to work on the music of the soul world where everything is translucent and opaque.

“One of the first tasks of composition would be to understand what it would sound like — what technique would be deployed and what instruments we’d use to bring it to life,” Reznor says of their composing process.

“Soul” required more exploration in their technique because the Great Before was a world that audiences had never been to before.
“There had to be clear definitions between the hectic pace of the world and falling through those layers and that next section,” Ross says.

“All of that is so much that we can’t even put it into words, but when Joe gets into the zone, the music speaks to that — the feeling of being connected to something bigger than us,” Batiste says.

Reznor and Ross discussed how ominous, friendly, or even terrifying the sound would be as Joe lands in that void.

Over the years, Reznor and Ross had developed ways of recording in their studio, such as bringing in different mic setups, voices and scraping sounds to create the foundations of the world.

“We might be using samples and recordings of instruments and processed them [in a way] that [highlights] … imperfections in humanity that it becomes an interesting response,” Reznor says. “It was very experimental and combinational that all worked together in the right key and we presented it to Pixar.”

At the turn of the console or a slide of the fader, “we would dial up this musical piece that felt malleable, and that became the boot print for Pete.”