On a Monday afternoon in early September, conductor Tim Davies is putting an 81-piece orchestra through its paces on the Warner Bros. scoring stage. On the bigscreen behind the musicians, a carrot-nosed snowman comforts an ailing princess inside an ice-covered castle in a scene from Disney’s upcoming film “Frozen.”

Behind the glass a few yards away, composer Christophe Beck listens carefully to a run-through of cue 5M55, “Anna and Olaf,” then offers a few suggestions to improve the performance: “More vibe and harp at bar 22. At 46, let’s not do the crescendo. Strings at 55 and 56, let’s have a little more. At 69, more bassoon; 73, mezzo-forte, not forte.” Another take and the 2½-minute cue is perfect.

Nearby, two directors, a producer and two music executives are all smiles as the music for the studio’s latest animated fairy tale nears completion.

“Frozen” is inspired by the Hans Christian Andersen tale “The Snow Queen” but takes a new direction in its story of two royal sisters, one of whom accidentally turns their kingdom into a land of snow and ice while the other attempts (with the help of a mountain man and his loyal reindeer) to break the spell of eternal winter.

Although there are eight songs in the film, nobody is calling it a musical. The studio is billing the film “a comedy-adventure” while one of the execs calls it “a movie with songs.” But privately, they express a level of enthusiasm that suggests the music of “Frozen” could be as classic as “Beauty and the Beast,” a Disney high-water mark from 22 years ago.

That’s because Disney is taking a cautious step forward by hiring the Tony-winning tunesmith responsible for the edgy, irreverent songs of “Avenue Q” and “The Book of Mormon,” Robert Lopez, along with his wife, Kristen Anderson-Lopez. And while an animated family film hardly offers the satirical form for which Lopez is best known, “I think they wanted us to be funny,” he says of his Disney collaborators.

Adds Anderson-Lopez: “We thought, this is our chance to make a really funny Disney princess — a real person that our generation has been waiting for: the one that’s not perfect, that gets pooped on, is clever and smart and has a sense of humor. I was really excited when (co-director) Jennifer Lee came on board. She had just come off ‘Wreck-It Ralph.’

Every chance we got to inject some real-girl-ness into it, we jumped on.”

The songwriters’ sense of humor comes to the fore in a pair of songs, one sung by the snowman and another by a pack of trolls, “but in the end what we really enjoyed doing was writing the sweeping romantic moments,” says Lopez.

One of those is the big empowerment number “Let It Go,” sung by “Wicked’s” Idina Menzel as the snow queen achieving her destiny in a stunningly realized ice palace. When the Lopezes wrote it, “we knew we had to build a story about that song,” says Lee, adding that Disney Animation chief creative officer John Lasseter “played it every day in his car for nine months straight.”

Still, they felt the pressure of such modern Disney classics as “The Little Mermaid” and “Beauty and the Beast,” whose Alan Menken-Howard Ashman songs not only won Oscars but are perceived as the Broadway-style standard for modern animated films. “Whenever we were feeling particularly lost, our battle cry was, ‘What would Ashman do?’ ” says Anderson-Lopez, “because he was such a force not only as a lyricist but he understood how to tell a story using music.”

The Lopezes have worked for Disney before. They wrote songs for the 2011 “Winnie the Pooh” and for a “Finding Nemo” Florida theme-park ride. This, however, was different: it was not just a big assignment, it took a year and a half of daily teleconferences, writing and rewriting.

All told, they wrote about 25 songs for the film, two-thirds of which were discarded along the way. The troll song (“Fixer-Upper,” about dating problematic people) was the fourth try. “We wrote this whole song that ended with a list of terrible things that could happen to your feet, including plantar warts and athlete’s foot,” admits Anderson-Lopez. “John Lasseter heard it and he was like, ‘What?! How did we get onto foot fungus?!’ ”

Disney spared no expense to achieve aural authenticity. Disney Music senior VP Tom MacDougall flew to Trondheim, Norway, to record a 35-voice female choir singing composer Frode Fjellheim’s “Eatnemen Vuelie,” which opens the film with an earthy Nordic sound. Beck’s underscore includes the Norwegian bukkehorn (ram’s horn) and Norwegian-born, L.A.-based singer Christine Hals’ “kulning,” a high-pitched vocal technique that was once used to call cattle down from Scandinavian mountain pastures.

The Lopezes, however, didn’t travel far for inspiration about snow, ice and wintry weather. “We don’t have to go anywhere,” says Lopez. “We live in New York City.”