David Finckel and Wu Han are chamber music royalty. On Sunday afternoon, the couple — heads of the Chamber Music Society of Lincoln Center, the ­Music@Menlo festival and the record company ArtistLed — reigned at the Barns at Wolf Trap with a wildly engaging performance of all five Beethoven cello sonatas.

Wu Han, the pianist, is the artistic adviser responsible for curating chamber music at Wolf Trap for the next two seasons — a signal change from last season’s curator, Lara St. John. Where St. John focused on diversity and folk music, Wu Han is concentrating on that hoariest of classical-music tropes, the city of Vienna. The program she has assembled offers much to delight lovers of the classical canon, performed by the cream of established chamber players: Haydn’s influence on Mozart, offered by the St. Lawrence String Quartet! A program of chamber music by Schubert! Another of Brahms and Dvorak! No question that these are all masterpieces, but these programs could have been planned in 1950.

Yet it was hard to listen to Wu Han enthuse about the upcoming season from the stage on Sunday and not share in her excitement. Throughout their careers, Finckel and Wu Han have represented exactly this: the gilt-edged calling card of the tradition-hallowed field, seemingly little touched by the mandate to diversify and reinvent but shot through with their palpable love of the music and their active desire to find more ways — festivals, recordings and teaching initiatives — of disseminating it. Rather than trying to change the face of the field, they are trying to make tradition more vivid and appealing (witness Wu Han’s colorful red robe, adorned with a sequined portrait of Frida Kahlo and tassels). They made a convincing case for their approach in the Beethoven sonatas, a beguiling pleasure from the first gentle, springy notes to the last wild fugue.

Finckel is an elder statesman of the field, having anchored the Emerson Quartet for more than three decades before deciding to break free and pursue a career with Wu Han that has turned out to be every bit as active and successful. (It is striking that their joint biography in the program is so filled with accomplishments that the Emerson Quartet doesn’t even get a mention.) Onstage, he remains an attentive and guiding presence, his face reflecting what’s happening in the music. Yet he’s not an emotive player. Rather, he offers didactic clarity in the way he distinguishes one phrase from another, switching on a dime from a passage of sweetness to digging into an allegro, gently articulating individual notes rather than succumbing to the lure of legato. Wu Han is more impetuous; yet together, the two present the kind of visceral familiarity and perfect synchronization born of years of shared music-making.

They also have preserved a key element of musical tradition that too often gets forgotten: joy. Time and again, one or the other of them would smile, at each other or at Beethoven, and I would realize that I was smiling along with them.

Chamber Music at the Barns continues on Jan. 11 with trios by Beethoven, Dohnanyi and Mozart.