Violinist Joshua Bell, Principal Pops Conductor Steven Reineke and soprano Kelli O'Hara, at the National Symphony Orchestra's 2014-2015 season opener at the Kennedy Center on Sept. 21. (Scott Suchman)

It’s been said that an orchestra’s season-opening gala should send artistic signals, stand up for new music, show high aspirations. Yet it’s really just a big party, a back-to-school gathering, a fundraiser, a chance to show off new gowns and suntans. On Sunday night, the National Symphony Orchestra chose to emphasize the celebratory and lighthearted side with a season-opening gala that signaled, above all, that this orchestra has several roles at the Kennedy Center, and one of them is to give pops concerts.

The gala was part of an opening weekend that ushered in the Kennedy Center’s new president, Deborah Rutter, with a bang, following the Washington National Opera’s opening with “Florencia in the Amazon” the night before. The center’s chairman, David Rubenstein, who seems to be enjoying his role more palpably with every season as his remarks from the stage at formal events get longer and funnier, gave a plug to “Florencia” to the NSO audience and encouraged them to attend the opera in what struck me as an unusual and welcome cross-promotion.

But then, the whole evening was a slightly unusual cross-promotion: Not since the days of Marvin Hamlisch has the orchestra celebrated its season with both of its conductors — on Sunday, music director Christoph Eschenbach and principal pops conductor Steven Reineke — in a single gala.

Rutter — who made her first, brief remarks to the Kennedy Center audience after Rubenstein spoke, expressing thanks and eagerness for future work together — got to see a lot of messy energy (starting with Bernstein’s “Candide” overture, which, as played by Eschenbach and the orchestra, demonstrated veritable golden retriever levels of muddy, amiable exuberance), and a couple of soloists at the top of their respective games.

The first half of the evening — the more classical half — featured violinist Joshua Bell in not one but two solo works, lilting in Saint-Saëns “Rondo Capriccioso” and digging into the Ravel “Tzigane,” playing with his signature lyrical insouciance but also with solidity. I’ve heard him equate “lighthearted” and “sloppy” in the past, and he didn’t do that at all Sunday night.

Violinist Joshua Bell was featured in two solos with the National Symphony Orchestra at the NSO's 2014-2015 season opener at the Kennedy Center. (Scott Suchman)

The second half, mainly under Reineke, showcased soprano Kelli O’Hara, who picked up on the Bernstein/”Candide” theme with the aria “Glitter and Be Gay.” Her high notes didn’t have the dazzling beauty that opera singers can manifest in this number, but her approach to the text, and the degree of meaning she was able to bring across, should be an object lesson to all would-be divas — as well as an illustration of some of the benefits of taking down the fences between musical genres once in a while.

O’Hara was melting in “Something Beautiful,” a song from a musical in progress by the team of Lynn Ahrens and Stephen Flaherty (whose new musical “Little Dancer” is a big focus of the Kennedy Center’s fall schedule), and mastered a medley of the chestnut “Autumn Leaves” and a song called “When October Goes,” which Barry Manilow wrote to lyrics by Johnny Mercer.

I went along with all of this, but her last number, a big, goopy, string-laden confection based on “La Vie en Rose,” with Bell joining her on stage, snapped me back into classical-curmudgeon mode, grumbling to myself that this was far too sugary and that unvarnished Edith Piaf was just fine with me, thank you very much.

This gala wasn’t for me, of course: I and my colleagues are supposed to write about artistry, not events, and are not thought to like this sort of thing. And certainly at some points in my life I would have wrung my hands about the decline of art and the selling out to commercial interests that such an opening represents. I would have been wrong, though, not least because I got as much out of O’Hara’s performance as I did out of the manic, excessive “La valse,” by Ravel, with which Eschenbach and the orchestra concluded the program. I would also have been wrong because the history of pops programs, and of concerts including supposedly lighter music, extends back many decades before my birth. And most of all, I would have been wrong because classical music, while it can convey some of the most profound and wrenching and monumental ideas and emotions in the human experience, is also, as we all too often forget, about enjoyment.

So, a good time was had by most. Welcome back.