Hip-hop artist Dessa describes her scheduled concerts with the Minnesota Orchestra this weekend as the most ambitious gigs of her career so far.

"I'm imagining this show as something like a cross between a rap gig, a classical concert and a TED talk," she said as she prepared for rehearsals.

Any of those three would be a challenge by itself; combining them introduces a multiplier effect. Dessa said she'll be performing familiar songs, but they will sound pretty different.

The lights of Orchestra Hall shine on the Minnesota Orchestra. Evan Frost | MPR News

"The familiar rap tune played by a full orchestra is not the familiar rap tune, just definitionally," she says.

She's planning something else that's different: The show will include a running narrative about neurology. About that part, she was a little cagey, not wanting to give away too much.

"I'll say: the neuroscientist Helen Fisher inspired the narrative thrust of the monologue I'll be delivering," she said. (Fisher is known for study of the neuroscience of leadership, and love.)

This weekend's concerts are the culmination of 18 months' work. To create the score for the show, Dessa collaborated with arranger Andy Thompson. He's worked with artists as diverse as Belle and Sebastian, Taylor Swift and Jeremy Messersmith.

Dessa prepares to rehearse with the Minnesota Orchestra inside Orchestra Hall in Minneapolis on Thursday. Evan Frost | MPR News

"Instead of thinking about the project as adding orchestral sounds to pop tunes, we really deconstructed everything and we burned the pop songs down and built up again from ash and viola," she said.

That was necessary not so much because of all the classical players involved, but because of the way rap is produced.

"Hip-hop has some repetitive sounds," she explained. She sang the word "hey," and then she sang it again, with a slight variation. The effect is different when rap artists use samples, she said, "if you take that recording and repeat it exactly, so that my breath sounds the same and my voice breaks the same."

This concert will be played live: no samples. Everything has to be produced on the fly, right down to Dessa's vocal effects.

The Dessa show makes great use of the famed acoustic cubes at the back of Orchestra Hall in Minneapolis. Euan Kerr | MPR News

And then there is what she calls the surround sound of being on stage with an orchestra. The music comes from all sides, unlike an amplified concert where singers are usually listening to monitor speakers at their feet while they perform.

"So even just that, of feeling awash in the music instead of leaning down towards your knees to better hear, it was totally different," she said. "The bodily sensations are different."

Dessa said the concerts may well attract some rap fans who are making their first trip to Orchestra Hall. But she's looking forward to the classical fans, too.

"I want to make sure people feel comfortable with champagne flutes or shooting whiskey at the bar," she said. She hopes "that both of those demographics are there ... having fun chatting with one other."

Dessa struts across the stage of Orchestra Hall. Evan Frost | MPR News

When asked if she's nervous about the concerts, she said of course — but she's excited by the opportunity to stretch herself with a world-class orchestra at her back.

"For me, it feels like transitioning from wakeboarding to being at the helm of a destroyer," she said. "It's a huge sound."

The concerts Friday and Saturday have been sold out for weeks. And perhaps as a sign of things to come, the orchestra has also engaged Dessa to play the Symphony Ball on June 24.