Alma Deutscher plays violin during a rehearsal in Vienna, Austria. Alma, 11, is a composer, pianist and violinist who wrote her first sonata five years ago and whose first full opera will have its world premiere next month. (Ronald Zak/AP)

Alma Deutscher is a composer, pianist and violinist who wrote her first sonata five years ago and whose first full opera will have its world premiere next month. She’s also 11 years old.

Mozart, who wrote his first symphony at age 8, may come to mind. But fresh from rehearsal, Alma laughs at the suggestion.

“I think for me it’s more interesting to be Alma” instead of Mozart, she says.

When not living music, the child prodigy from Dorking, England, is busy scraping her knees climbing trees, meeting friends on the playground or swimming.

But when focused on her passion, she’s all business.

Rehearsing her German-language opera “Cinderella” recently, Alma gave instructions and sang phrases in a clear soprano, switching from piano to violin as she accompanied the soloists. It seemed effortless, but the girl in the red woolen tights and floral print dress was clearly in charge — and enjoying running the show.

“I can’t wait until everything will come together,” she says, looking ahead to “Cinderella’s” premiere in Vienna, Austria, on December 29. “I dream about how it’s going to look like on the stage.”

Conductor Zubin Mehta, who is helping to stage the opera, is only one of today’s musical greats impressed by her talent. Violinist Anne-Sophie Mutter describes Alma’s performing and composing talents as “absolutely extraordinary.”

Alma Deutscher

Alma’s father, Guy Deutscher (DOY-chur), remembers her “singing almost before she started speaking” — and one day, coming home from a toddlers’ party singing a nursery rhyme in perfect pitch, with all the notes just right.

Drives to the supermarket turned into tests of will, he says. Alma, normally “an extremely good-natured girl,” started screaming if her parents tried to get out of the car while music she loved was still playing.

Alma recalls falling in love with music sometime after age 2. She heard a lullaby by the composer Richard Strauss, she says, and she was dumbfounded.

“After it finished, I asked my parents, ‘How can music be so beautiful?’ Then I started having ideas of my own. I’d just sit down at the piano. I didn’t write my ideas down, I just had them in my head, and I played them. I was 4.”

The music comes on its own, says Alma.

“If I try to sit down and think, ‘now I must get inspiration,’ then I just don’t get inspiration, it doesn’t come to me,” she explains.

“But when I am not thinking about it at all, when I’m just relaxing, skipping in the garden and just about to fall asleep or just about to wake up — or when I’m actually in a dream — then I get the beautiful inspiration that I put together.”

Future plans include a symphony. She has started a book, which she wants made into a film, complete with her own musical score. Alma says it features ghosts riding “night mares” and poisoning dreams by breathing toxic fumes.

For now, the main focus is on “Cinderella.” The title character is a composer who is “a bit like me,” Alma says. The stepmother character is an opera director. The two stepsisters are snobbish divas, and the prince is a poet who finds Cinderella through a melody she wrote.

“The prince is haunted by it,” Alma exclaims. “He finally has the brainwave to search everywhere in the kingdom, and he will sing the beginning of the melody and only the girl who can continue it will be the one that he’s looking for.”

She says that she stole the most beautiful vocal solo from someone else — but “Antonin Yellowsink” doesn’t really mind.

“He’s my imaginary composer,” Alma says with a giggle. “I often dream about him.”

Alma Deutscher