Soprano Barbara Hannigan is a hugely improbable opera singer on many fronts — until she explains it all and starts making sense.

The provocative, singularly talented 46-year-old singer, who gives a Philadelphia Chamber Music Society recital at 8 p.m. Tuesday at the Kimmel Center's Perelman Theater, navigates some of the toughest music ever written and isn't the worse for wear.  She's also a conductor. And sings at the same time.

Her modern-music repertoire used to be box office suicide. Now, it's the basis of her international career.

Take her Tuesday program, for example. It's full of names that don't exactly inspire affection, like Schoenberg, Webern, and Berg.  Then she tells you the opus numbers — all of them early, before those composers dove into atonality. The program was devised by  79-year-old pianist Reinbert de Leeuw, a legend in Dutch new-music circles. If you're OK with Wagner, you'll be OK with this.

"It's decadent in the original use of the word: decay, as in the decay of harmony.  It's not into the new world yet, but you can see it through the mists," Hannigan said in a phone interview from Washington, where her current tour started. "The program is late-romantic … but for me, everything is romantic, extremely emotional, and that's probably why I've been able to reach such an audience with my repertoire."

Still, looking over the program's stylistic progression, couldn't there have been a place for Mozart? Would that be so onerous? "The normal recital format that we learned in school — a little bit of this and that, and tie it together dramaturgically — has never interested me," she said.

Queen of the not

One of many urban legends about Hannigan is that she turns down offers to sing the vocally intricate Queen of the Night in Mozart's The Magic Flute because it's too easy. That's not quite right. She didn't want to be typecast in that kind of specialized repertoire. "I would go nuts," she says.

Instead, she's typecast as an uber-modernist. In opera, she's best known for the daunting, truth-telling title role in Berg's Lulu — a target for predatory men. Such music is her mission. No wonder she didn't have a serious agent until six years ago. "I feel like I'm in a service industry, and I know it's an important service to contemporary music," she says.

Surely, there were those who tried to talk her out of this path.

"I don't think anyone has tried to dissuade me. I'm not in anybody's way or taking anybody's place. There were some people who couldn't really comprehend it," she said. "I sang my first world premiere when I was 17. I found like-minded people — dancers and visual artists. It was a community of oddballs, but it's still my community."

That explains the keen sense of self-presentation that marked her 2013 Philadelphia Orchestra debut: She sang Ligeti's Mysteries of the Macabre, portraying a police chief and dressed as a dominatrix. Also, she didn't stick to the usual circumscribed soloist zone on the Verizon Hall stage.

Behind those choices is something more than an adventurous nature. Hannigan's love and understanding for modern music is such that she hums Pierre Boulez's disjointed vocal lines in her everyday life.

You'd suppose such a creature would have to be a hardcore urbanite. But, in fact, Hannigan is from Nova Scotia, and she embarked on her current path only after a late-teenage relocation to the University of Toronto. Those years in the Halifax area were key to her. "Absolutely, it was not wasted time. We didn't have distractions. We got together on our breaks and on weekends and read through music," she says. "I wouldn't have had it any other way."

Like walking and chewing gum

Hannigan made her conducting debut in 2011. The singer/conductor combination isn't all that unusual, although doing both at the same time certainly is. "The good thing is that I don't have to cue myself," she said.

Rather than conduct with her back to the audience, she has her back to the orchestra when singing. She challenges the orchestra to adjust under the heading of raising everybody's game.

"I find it's most successful when I'm hardly conducting at all. We're in a situation of being inside the music in a way we're not used to experiencing. It's very psychological," she says. "You have to have a connection with the orchestra.

"Sometimes, when an orchestra and I aren't having a connection, I can't figure out why," she says. "It's interesting. How could they not adore you? But it's like dating."

As for other conductors, she tends to work with fellow adventurers, such as Simon Rattle and Kent Nagano. In recent years, she has even sung Mozart's Don Giovanni, in the role of Donna Anna, though only with the right creative team.

She has also been singing Debussy's Pelleas et Melisande. It probably uses only a fraction of her voice but offers endless depths with its mysterious French symbolist narrative. Her new solo album, Crazy Girl Crazy, has her singing Gershwin — alongside some Viennese Berg.

The paradox is that the more she expands her world, the lonelier it gets.

"I can't call somebody up and say, 'What did you do in this kind of situation?' I can't ask for advice from one person," she said. "I think I have survival instincts. Of course, I have a singing teacher. But it's lonely to be on the road, no matter what."

But let's not feel too sorry for her, because once she arrives home, she's in Paris.

"I love somebody in Paris," she says. "I love Paris, and so loving somebody in Paris is a killer combination."

Barbara Hannigan

Performing in recital with pianist Reinbert de Leeuw 8 p.m. Tuesday at the Kimmel Center's Perelman Theater, 300 S. Broad St.

Tickets: $30.

Information: 215-569-8080 or www.pcmsconcerts.org.