Emil de Cou, associate conductor of the National Symphony Orchestra. (Scott Suchman)

This weekend, the Virginia Chamber Orchestra is giving a couple of premieres. What’s notable about them is they’re by Claude Debussy, whose 150th birthday is this year. Debussy’s sole opera, “Pelleas et Melisande,” remains a distinctive standout in the operatic canon, but the composer took a few stabs at dramatic vocal writing before it, including the unfinished opus “Diane au bois,” about the god Eros’s seduction of the chaste Diana. With “Diane,” as later with “Pelleas,” Debussy started writing at a point that interested him, the love duet — “something,” says Paul Meecham, the president and CEO of the Baltimore Symphony Orchestra, “that he could get his teeth into.”

Meecham is not usually concerned with the Virginia Chamber Orchestra, but he has a direct interest in the premieres. One of them, an orchestration of the opera’s overture, is by his old friend Emil de Cou, who when he’s not leading the National Symphony Orchestra’s summer concerts at Wolf Trap and the Pacific Northwest Ballet Orchestra is the VCO’s music director. And the other, an orchestration of the love duet, is by Meecham himself.

Orchestral administrators are not generally known for having this level of musical ability. Nor are they noted for their diffidence. “You don’t often run across modest people in the music world,” observes de Cou, who found out about Meecham’s Debussy work when the two overlapped at the San Francisco Symphony in the 1990s, where Meecham was general manager. But Meecham, who trained as a pianist and violinist, downplays his musicological past. He did his master’s thesis on Debussy’s unpublished vocal works, and orchestrated the love duet as a part of the project.

“I must have told Emil in a weak moment,” Meecham now says of the events that led to his first — and, he insists, last — American orchestral performance. “Years later, he called me up and said, ‘What about “Diane”?’ I said, ‘You can’t be serious,’ and dug the thing up.”

De Cou is no stranger to Debussy reconstruction. His “Debussy: Rediscovered” recording, made in 2000, includes his own orchestration of the odd “Printemps — Suite Symphonique,” which he subsequently performed at the Washington National Cathedral with the NSO in 2003. “Printemps,” written, like “Diane,” while Debussy was living in Rome as a recipient of the Prix de Rome in 1885 and 1886, was conceived as an orchestral work in which human voices — a wordless chorus and soloists — would be used simply as instruments, to convey a particular kind of sound and tonal color rather than specific verbal meanings. Debussy, however, never got around to orchestrating it, and the composer whom he authorized to complete the work, Henri Busser, opted to take a more orthodox route, without the chorus.

“Diane au bois” was also an unusual, experimental work. Debussy actually began it when he was in the running for the Prix de Rome, but letters have survived between Debussy and his teacher that Meecham says, “suggests that he did not submit it because it was going to be too advanced.” Not that the score is wholly unorthodox: Meecham calls the final duet “very conventional. What’s most interesting is the music leading up to it, the chase.” The scene opens with Eros sitting on stage, playing a flute; Diana comes running in, as if drawn in spite of herself. “There’s definitely a connection between that” music, Meecham says, “and [“Prelude to the Afternoon of a Faun”] and the first scene of Pelleas,” both of which were written in 1893, several years later.

Both arrangements are being heard here for the first time, but this concert does not represent the first-ever “Diane au bois” performance. Blame the tenor. The VCO’s program was originally scheduled for October, but the orchestra was unable to locate a tenor soloist, so it switched its season around and played the program meant for May first. In the meantime, another orchestration and reconstruction of “Diane au bois,” prepared by the leading Debussy scholars Robert Orledge and Richard Langham Smith, had its world premiere in February at London’s Royal College of Music. De Cou is philosophical about losing bragging rights. After all, he says, it was a book by Orledge that alerted him to the existence of “Diane au bois” in the first place.

Fans of unusual Debussy work are being catered to this week with two concerts. In addition to the VCO’s performance, the National Philharmonic, which is concluding its own Debussy festival, and its season, with “The Martyrdom of San Sebastian,” a sprawling, confusing work filled with sensual mysticism and some stunning orchestral writing. Critical opinion remains divided about whether this piece, written essentially as incidental music and first performed in 1912, is a failure or a neglected masterpiece.

It’s not hard, de Cou points out, to find Debussy rarities and expand the audience’s vision of the composer. “The music that people know of Debussy — you can count it on the fingers of one hand. Anything you can add to the Debussy canon, it’s a good thing.

As for Meecham, he’s not looking to quit his day job. “This is a one-off and it will remain a one-off,” he says. But he’ll be attending Sunday’s concert in an unfamiliar role: on the creative side. “I’m very intrigued,” he says, “to see how it will stand up.”

The Virginia Chamber Orchestra

performs its “Sunday in the Woods” concert at 4 p.m. Sunday at Ernst Community Cultural Center, 8333 Little River Tpk., Annandale. www.virginiachamberorchestra.org.

The National Philharmonic

performs “The Martyrdom of St. Sebastian” at 8 p.m. Saturday at the Music Center at Strathmore, 5301 Tuckerman Lane, North Bethesda. www.nationalphilharmonic.org.