It was that rarest of sights when I walked into the Cleveland Orchestra’s hall on Sunday afternoon: a dark curtain drawn across the stage.

Rare, that is, in a concert hall. Orchestras don’t tend to have dramatic unveilings before they start to play. And while Cleveland has done near-annual opera presentations over the past two decades, the ensemble has almost always been onstage alongside the singers, as the stagings have worked around (and sometimes incorporated) the presence of dozens of players.

But for Mozart’s “The Magic Flute,” which ended a sold-out four-performance run at Severance Music Center on Sunday, the orchestra was lowered into an honest-to-goodness pit, and the curtain was closed at the start, just as it would have been in an opera house.

It was a reminder that opera — expensive to put on and not to everyone’s taste, though with a passionate fan base — has been ever harder to find in American cities. And a reminder that orchestras can — and should! — summon the resources to fill even a bit of that gap.

As the Cleveland Orchestra’s president and chief executive, André Gremillet, said in an interview, “This city doesn’t otherwise have world-class opera.” Cleveland Opera, a company that did present world-class offerings for several decades, faded away about 15 years ago, and a couple of companies left in its wake offer just a smattering of smaller-scale performances.

And yet there is a hunger for the art form, and an opportunity for orchestras around the country to expand their audiences. “There are people who are not here every week,” Gremillet said, “who will come to the opera — and more than once.”

It helps that Cleveland has, in its music director, Franz Welser-Möst, a deeply experienced opera conductor who for a time shared his responsibilities here with a leadership position at the Vienna State Opera.

Cast with fresh, youthful voices and played with poised transparency by one of the world’s great orchestras, “The Magic Flute” was the 20th opera presentation of Welser-Möst’s Cleveland career, which will end in 2027 after a quarter-century — astonishing longevity in today’s music world.

Seating-in-the-round halls like Walt Disney Concert Hall in Los Angeles and David Geffen Hall in New York lend themselves to experimental stagings like the high-tech version of Meredith Monk’s “Atlas” in Los Angeles in 2019, but don’t allow for traditional elements like, well, a curtain. Severance, with its silvery Art Deco touches, is a more old-school theatrical space, and Nikolaus Habjan’s “Flute” staging echoed that traditional quality, if little of the hall’s magical atmosphere.

Tricked out with a few cute puppets, Habjan’s work was straightforward and plain, even a tad bland, and perhaps overly reliant on that curtain, which opened and closed constantly and was enthusiastically incorporated into the action. The production was less enchanting than Yuval Sharon’s Cleveland staging of Janacek’s “The Cunning Little Vixen,” with singers’ heads popping out of a wall of animation, or his spare, ominous “Pelléas et Mélisande.”

Denise Heschl’s “Flute” costumes offered variants on formal wear; Heike Vollmer’s set relied heavily on a scaffold-style platform that has grown familiar to Cleveland audiences from recent semi-staged opera performances, kitted out this time with some bars of white light. Only Paul Grilj’s lighting really added to the piece, occasionally filling the hall with a haunting pale grayness.

But certainly nothing in the production distracted from the superb musical performance. Among the best reasons to do opera in concert halls is that they tend to be more intimate (at least relatively) than American opera houses.

With 2,000 seats, Severance is about half the size of the Metropolitan Opera in New York, and far smaller than the other big legacy opera theaters in Chicago and San Francisco. (Texas’s two major houses, in Houston and Dallas, buck that state’s reputation for grandiosity and are happily closer in scale to Severance.)

This allowed the “Flute” performances to have unaffected clarity and restraint, without pushing. Julian Prégardien was a plangent Tamino and Christina Landshamer a sweet-voiced Pamina. Kathryn Lewek, one of the world’s reigning Queens of the Night, managed both super-high precision and considerable warmth. Ludwig Mittelhammer was a Papageno whose clowning never tipped into overdone mugging; Tareq Nazmi, a smoothly resonant Sarastro; and Dashon Burton, a rich-toned Speaker.

And while not a typical virtuosic orchestral showpiece, “The Magic Flute” displays Cleveland’s wondrous cohesion and elegance. This ensemble’s glory is in the self-effacing details: the gentle piquancy of the strings plucking as the Three Boys were introduced; the mellowness of the horn and bassoon combining as Tamino and Pamina embarked on their trials.

Welser-Möst’s music-making tends brisk, but in this case it felt less fast than smoothly flowing, and not without weight or fullness. There was airy lucidity in the choral singing, too, which, under Lisa Wong’s direction, had nuance and a clarity of diction that matched the soloists’.

Cleveland’s operas haven’t hewed to the standard repertory, wandering as far toward rarities as Strauss’s “Daphne.” This has led to stark differences in terms of audience draws: Puccini’s “La Fanciulla del West” was decidedly not sold out last year, while “The Magic Flute” brought full houses (and a lot of families). Early in June, the Philadelphia Orchestra is performing “La Bohème,” using a beloved title not just to attract new audiences but also simply to bring in the crowds that have taken a long time to return to concerts since the pandemic.

Welser-Möst and Cleveland are taking a different tack, doubling down on more recondite works. Next season will bring a concert version of Janacek’s “Jenufa,” and the orchestra said on Monday that 2025-26 will include Beethoven’s “Fidelio” in concert, and that Welser-Möst’s final season the following year will culminate in a staging of Strauss’s “Die Frau Ohne Schatten.”

All this is, of course, not cheap. Gremillet estimated that a staged production costs about twice as much as presenting the same opera in concert, which is itself far more expensive than a normal symphonic weekend.

But doing it can deepen the playing of even a great ensemble. “This orchestra has always been great,” Welser-Möst said in an interview. “But what I wanted from them when I started was more flexibility, and a more singing sound. And after we did ‘Rusalka,’ Dvorak’s Ninth was a different piece for them. After ‘Rosenkavalier,’ ‘Till Eulenspiegel’ was a different piece for them.”

As the orchestra searches for Welser-Möst’s successor, Gremillet gave a hint that he’d prefer a music director who can maintain these regular presentations as a pillar of the Cleveland season. “There’s something about experience conducting opera,” he said, “that to me signals a complete conductor.”

And there’s something about presenting opera that signals, to me, a complete orchestra.