Violinist Gatto at Kimmel Center

The Chamber Orchestra of Philadelphia has long been a window on young European talent: With post-9/11 security, many such 21st-century artists are not heard here with much frequency on anything other than recordings.

So although violinist Lorenzo Gatto was introduced Monday at the Kimmel Center as a rising name in Europe (he placed second in the 2009 Queen Elisabeth Competition), one can safely say that, artistically, he has risen. His encore alone - Paganini's Caprice No. 5, played with an effortlessness that showed you the piece isn't just fireworks but an interestingly quirky piece of music - reflected an inordinate level of accomplishment and intelligence.

The Beethoven Violin Concerto was his main platform, and a bold one considering that it occupied the program's second half and has often been a piece that musicians don't take on until middle age. But it's fashionable these days for young musicians to dive off the deep end, and though Gatto emerged with all sorts of interpretive finds, the slow tempos that allowed him to do so weren't so good for the orchestra.

Particularly during the first movement, the players had particularly expansive musical ideas to sustain. With less than half the numbers of the Philadelphia Orchestra (and with some Chamber Orchestra regulars absent because they are playing in Opera Company of Philadelphia's current La Boheme), music director Dirk Brossé had the group laboring to make rhetorical points, one side effect being ham-fisted playing from the brass.

However, the tempos made sense when Gatto was playing. His radiant, unforced sound yielded expressions of beauty, the lofty, ozone-layer sort in which this concerto travels. No passing note was brushed over, which could have seemed pedantic had Gatto lacked a firm grip on the concerto's larger scheme.

Also, his technique is such that the finest shadings are available to him, justifying his choice of tempos. He's perfectly at home with the concerto's nobility, though his recordings of lesser-known works by Enescu and Martinu show he's even better when trafficking in mystery.

The concert opened with Haydn's Symphony No. 96, and slow tempos were briefly an issue in the Andante movement, until conductor Brossé revealed a richness in the scoring that's often lost in more homogenized performances. Brossé opened the concert with one of his own pieces, the 2003 Sire for string orchestra, prefaced by an explanation of its subtext and construction (royalty, mathematics, etc.), often sounding like an architect talking about scaffolding. What unfolded was a mellifluous, lyrical piece that spoke well for itself - like the soundtrack to a movie you didn't have to see to enjoy.