The two concertos are studies in contrasts. Mozart's Horn Concerto No. 2 is part of the standard repertoire. If you're a horn player, says Jennifer Montone, "You've been playing it as long as you've been playing the instrument." Light, lively, it's Mozart with all the rhythmic thrills and delights one expects of him. "It's very fun to both play and listen to," says Montone.

Hindemith's Horn Concerto has been performed only once before by the Saint Louis Symphony Orchestra, with soloist Barry Tuckwell and conductor Leonard Slatkin in 1983. Few recordings of the work exist. Rather than delivering a big virtuosic finish, as with so many concertos, the Hindemith "ends slowly," says Montone, "so it has to be powerful in a different way. It's a very emotional piece."

Whereas Mozart is "so natural that the phrasings have become almost traditional, and I naturally lean their way," Montone continues, the Hindemith lacks any "organic predictability. With Hindemith you can choose to phrase things many different ways. One night I sang through the first three lines of the first movement and phrased it eight different ways. It's crazy!"

Montone, who joined the SLSO as principal horn in 2003, has proven herself up to such challenges again and again. Her tone, her acute ear, her rhythmic dexterity, and her technical facility have been recognized by audiences and critics in St. Louis and at Carnegie Hall. In a brief time with the orchestra her sound has become one of its distinctive assets‹altogether recognizable and compelling. She's become a musician you come to Powell Symphony Hall to hear, no matter the program.

A freak injury from an auto accident forced her to take disability leave through part of last season. Because of resultant muscle strains it pained her to play, but now she is down to "one doctor visit a week or so and just two sets of physical-therapy exercises every day. When I play in the low register for a sustained amount of time it hurts, but luckily I've got great colleagues to do all that. So it's fine," she says with a plucky grin.

Her SLSO solo debut is set for February 24 and 25, with guest conductor Roberto Minczuk (who is also a fellow horn player), and Montone is excited about the challenges of bringing out the beauty in the two contrasting concertos. Two months before her performance she's asking herself a lot of questions about works both familiar and unfamiliar. "Especially with Mozart," she says, "because he wrote for a smaller horn, it's easy to play too loud, too big, and the piece stops sounding like Mozart. You can get out of the style quickly. I want to find out how to have flair without going outside of the appropriate Mozart style. And then again, what is that? What is the appropriate Mozart style?"

The Mozart concerto may be familiar, but its very familiarity brings up special challenges. "I read through the Mozart periodically," Montone says, "to remind myself what it's like. The problem with that piece is that you've played it since you were very young. So there are a lot of bad habits, a lot of very ignorant and basic things that you did then because you didn't have the technical control."

If preparing for Mozart means erasing bad habits, the Hindemith calls for the discovery of the very core of the work. For Montone, putting down the horn and, again, singing through the piece helps her through the trickier parts.

"Singing through it helps because there are so many details involved in horn playing that get in the way of interpretation," Montone explains. "There are a lot of internal things going on when you play the horn‹your air, what's happening inside of your mouth‹technical variables that make it difficult to try to phrase the best way, to get all the important details in the music.

"There are so many ways to teach horn, but I find singing helps to put the idea in your head and let the body try to get there without trying to micromanage the physical aspects as much. That's the method that helps me, because when I get too involved in the technical aspects I get too confused and then I get demoralized." Montone laughs at her own description. She's not one who gets demoralized for very long.

"I advise my students to sing along with the radio really loudly to learn about pitch issues in an orchestra. There's something about the way you have to sing from the core of your throat when you're really belting along with the radio that is similar to trying to blend with another instrument and play in tune. Also, singing is a good tool for breathing and trying to be soloistic and musical, that makes it easier to bring that approach to the horn."

Erasing the bad habits, singing to find the right phrasings, overcoming the technical hurdles to get to the interpretive decisions‹Montone has her preparatory path set before her. In doing so, she hasn't neglected the joy involved. "I'm thrilled as an orchestral musician to get to do solo work as well. I'm really loving playing everything."

Eddie Silva is the publications manager of the Saint Louis Symphony Orchestra.