Custom-made instruments are the key to scoring for composers Anže Rozman, Kara Talve and musician Russell Emanuel.

Emanuel is a co-founder of the composer collective Bleeding Fingers Music along with Hans Zimmer and Steven Kofsky. Among the shows they’ve worked on that could grab voters’ attention are Apple TV’s “Prehistoric Planet.”

In the show’s prior season, they created custom instruments made from fossils, bones and dinosaur skull replicas and married them to a standard orchestra to create an otherworldly soundscape.

For the third season, “Ice Age,” Talve and Rozman wanted to bring audiences into more familiar territory, especially since humans were evolving and existing at that time. “The score is slightly off, but it’s much more emotional,” Rozman says.

The first episode, “The Big Freeze,” features a woolly mammoth giving birth in the blizzard. Talve explains that one discussion was about how to show the scale of the animals and highlight it through music.

To achieve the score’s heavier and darker sound, the team removed high flutes, violins and brass. The composers also try to bring something unique to their scoring process. “We had a wall of cellos in a semicircle and double basses. We recorded an octobass, which is a huge double bass,” Rozman says.

The instrument was so big that the player needed to stand on a stool to play it. “That gave us the rumbly, low feeling for the mammoths,” he says. The sounds of the terror bird (phorusrhacids) was based on a prototype, which was modeled on the larynx of an extinct terror bird species. But they took it to the next level, and the Triceratone was born, a wind instrument that created the guttural sound needed for the bird.

The highlight of the score was the Divje Babe flute, discovered in 1995 at the Divje Babe archeological site in Slovenia. It’s a bear femur with holes, thought be a Paleolithic instrument. “Our friend has a replica. We went into the caverns of the Postojna Cave [in Slovenia] and recorded it,” says Rozman. “It’s a very eerie sound that immediately transports the listener back in time.”

Talve worked closely with Emanuel on another Emmy contending score: “The Simpsons: Treehouse of Horror.” The episode is split into three segments, the first titled “The Last Days of Crisco,” which is the story of Fatberg the monster, who draws fat from his victims. It also parodies “Jaws.”

The idea that Crisco was underground lent itself to the low, rumbly sound of the score. “You know he’s coming,” says Talve of Fatberg, and so the go-to sound was a “huge orchestra with big, over-the-top brass.”

For the show’s third segment, “Plastic World,” flute player Pedro Eustache and his arsenal of woodwind instruments were brought in — but he, too, custom-made his instruments.

“He had made this giant thing out of PVC pipe, and he was a key part of the sound of ‘Plastic World,’” Emanuel says.

Now in its 37th season, “The Simpsons” has its distinct sound, so that was something Talve kept in mind when scoring “Treehouse of Horrors.” “It’s always bringing those worlds together. “What does ‘Late Night With the Devil’ sound like if it’s in Springfield?” he asks.

Emanuel adds it’s the passion of the show’s creative team that propels them forward. “It’s a big piece of why the score still sounds fresh,” he says. “We have incredible spotting sessions with them, and you just feel there’s so much DNA that still lives on.”

He adds that the producers, writers and artists “really live it, and I think that emanates back to us. They’re a big part of why the score is so successful.”

The Bleeding Fingers’ next project might be their biggest undertaking: the “Harry Potter” series for HBO. “It’s a privilege,” says Emanuel. “It feels like you’re watching TV history being made.”