The Järvi conducting dynasty (father Neeme, sons Paavo and Kristjan) has blanketed the profession, one or another of them popping up seemingly everywhere an orchestra can be found in Europe or the United States. Kristjan, a youthful 31, trained at the Manhattan School of Music and the University of Michigan and is gradually building up a solid career, guest-conducting such top orchestras as the Berlin Philharmonic, London Symphony and Orchestre de Paris. His engagement with the National Symphony Orchestra at the Kennedy Center this week is his second, after a 2010 debut, and it was underwhelming.

In a program of melodious 20th-century pieces, Järvi came across as sort of a “post-modern” conductor, with hip-swaying and shoulder-shimmying that wouldn’t be out of place in a dance club and curlicues with the baton that conveyed something like, “The beat’s in there somewhere — have fun with it!”

But there was not a lot of musical substance behind all this. In George Enescu’s potboiler, the Rumanian Rhapsody No. 1, Järvi never tried to shape the endless oom-pah accompaniment, letting it remain just a lumbering, taurine mess. He conducted the waltz movement from Rachmaninoff’s “Symphonic Dances” in one beat to the bar throughout, even in the slowest sections; those playing the crucial off-beats were left to guess at his exact intentions. And I saw no effort whatsoever to deal with the most pervasive problem with this orchestra in this hall: the ease with which the brass and percussion bury the rest of the players.

Jennifer Koh, the soloist in Samuel Barber’s Violin Concerto, was victimized by this. She is a visually intense player but does not have an especially large or rich sound to begin with; here she was forced to push what she had to the limit, in an often-futile attempt to cut through the mush behind her. The tone became dry and forced, particularly unfortunate in this piece, which emphasizes the emotional, lyrical side of the instrument — the slow movement, with its big oboe solo, is a clear tip of the hat to Brahms. The finale, though, is a breathless moto perpetuo, quite jarring after the first two movements. Koh certainly seemed to be on top of the frantic passage work (when you could hear her), but the orchestra was still trying to catch up.

That said, for the most part the NSO played impressively Thursday night despite the unfocused leadership. The many wind solos in the Enescu and Rachmaninoff were solid and strongly characterized. Concertmistress Nurit Bar-Josef, in just a brief solo in the Rachmaninoff waltz, displayed a sonority of almost lurid force that the evening’s guest soloist had never achieved. The massed strings rang out with enjoyable power in the big tunes.

Järvi’s shortcomings — which include an energetic beat that nonetheless often fails to convey the character of what’s about to come — may well solidify with more experience. And now that they’ve gotten through it once, the NSO may well cohere better around him at Friday and Saturday’s performances.

Battey is a freelance writer.