It sneaks into the air, rising from within the trumpet section, and soon spreads to the rest of the brass. The mood is so contemplative that it takes the audience a moment to realize what the tune is, and to get to its feet.

Otto-Werner Mueller's take on the Star-Spangled Banner is more than an orchestration. It's a total mood changer, and it's probably safe to say that after the year we've had in politics, it lands in the ear as a salutary reminder of a gentler national character from not that long ago.

Mueller's piece has popped up on Curtis concerts before. The first time I noticed it was not long after 9/11. It opened Sunday afternoon's first appearance this season of the Curtis Institute of Music orchestra, and now it is also an homage. Mueller, Curtis' longtime conducting pedagogue, died in February.

The Curtis orchestra's concert this February will be dedicated to his memory. But this was a better way of remembering Mueller, who was always urging students toward an ever-higher level of consideration for orchestral sound. By the time his Star-Spangled Banner brings in the strings, the orchestra is aglow – a warm, Brahmsian hand on our national soul. Whatever else it represents in football stadiums, and however its lyrics in the hardly known third stanza may be scanned now for racist overtones, Sunday's Muellerized version was a view of America at its most benevolent. No national anthem has ever removed itself as far from jingoism as this one.

The entire concert was an essay on the power of orchestral color. I couldn't say that conductor Corrado Rovaris brought any special sensibilities in this regard to the Ravel orchestration of Mussorgsky's Pictures at an Exhibition. What he did do exceedingly well, however, was to manage with unusual grace transitional moments, those critical turns where one phrase is ending and another beginning. This sensitivity perhaps stems from being an opera conductor (he was on loan from Opera Philadelphia, where he is music director). You couldn't hope to hear a more correct and pristine trumpet solo than the one turned in by Steven Franklin in the "Samuel Goldenberg and Schmuyle" section. Conducting fellow Conner Gray Covington led the Star-Spangled Banner, as well as an incisive reading of Boulez's Notations.

The triumph of the concert, though, was Rovaris' finely shaped performance of Ravel's L'enfant et les Sortilèges. The short opera has more than two dozen singing roles, and this performance with the Curtis opera department – minimally staged, with modest costumes, by director Christopher Mirto – was notable for the number of singers able to fill voice with character.

It's the story of a boy whose rudeness comes back to haunt him by way of a parade of singing woodland creatures and household objects, from tree frog to tea cup. Think of it as an absurd Beauty and the Beast mixed with Ravel songs, one of the piano concertos, and a drop in from the composer's Valses nobles et sentimentales. Mezzo-soprano Kendra Broom was the boy, singing with great style and presence.

This is also the kind of piece for orchestra stocked with such invention and fleeting beauty that you wish it came punctuated by periods of silence to absorb it all. The phenomenon was emphasized by a high level of playing: a wild trombone solo by János Sutyák, the incredible facility of pianist Michael Davidman, the hushed section of pastoral drumbeats and winds, and the silken sound of flutist Emma Resmini (in her standing solo).

This was an ensemble contributing as much to the idea of characterization as the singers: in turns sentimental, ridiculous, taunting and sincere.