Hmmmm. To ding a performance by the Preservation Hall Jazz Band for being maybe just a bit too genteel wouldn’t make a lot of sense, would it? So we’ll just say that last night’s not-quite-two-hour concert by the venerated New Orleans jazz outfit’s current lineup at the Barns of Wolf Trap took a while to get cooking. But band and audience finally clicked after intermission, the players eventually convincing the initially staid crowd to rise and follow them in a room-orbiting conga line before mounting the World’s Most Polite Stage Invasion.

In the hour-long first set, the band seemed to be having more fun than the audience. Nothing wrong with that, necessarily, though there probably is something wrong with Preservation Hall Director Ben Jaffe stopping the show for what felt like 15 minutes to introduce each member of the band after they’d barely been on stage for that long. Sure, want to hear about the players – there’s a lot of talent and a lot of history up there - but after they’ve, you know, played a bit, OK?

Ben is the son of Allan Jaffe, who founded the titular Preservation Hall at 726 St. Peter Street in New Orleans’s French Quarter, from which the group takes its name. Besides playing tuba in the band (as Ben does now), the elder Jaffe also hired musicians to perform at his hall and, starting in 1963, to tour as The Preservation Hall Jazz Band, paying them full union scale for their labors.

The devastation wrought by Hurricane Katrina in 2005, and the Federal government’s abysmal response in its aftermath, lend an undeniable urgency to the prospect of a group of mostly Nawlins-bred players touring the country reminding audiences of the city’s vast contributions to American music and culture.

With the exception of Jaffe's remarks during those lengthy band intros, all that was left as subtext last night. Instead, the ensemble served up stylish, tasteful readings of light-hearted standards. Singer/saxophonist Clint Maedgen crooned “I Can’t Give You Anything But Love” for a couple celebrating their 25th wedding anniversary, and trumpeter/emcee Mark Braud led an audience-participatory “Shake That Thing” to close the first set. After intermission, “The Tiger Rag” featured an unbroken, gap-toothed grin – and an epic drum solo – from Shannon Powell. Bassist Walter Payton contributed a Louis Armstrong-like lead vocal, and some dance moves I wish I hadn’t seen, to “I Wish I Could Shimmy Like My Sister Kate” before ceding the stage to pianist Rickie Monie, whose solo piece pretty much trounced everything we’d heard up to that point.

A song of mourning for a just-deceased friend came next, performed without lights save for a spotlight aimed at the players’ feet as they circled the stage. Powell sang Professor Longhair’s “Go to the Mardi Gras”, which benefited nicely from some unmiked backing vocals from the rest of the group. After the Ozomatli-style closing medley, during which Powell slyly dropped in a few lines of "Sex Machine" and Sir Mix a Lot’s deathless “Baby’s Got Back”, about a quarter of the crowd bailed*, leaving a lot of empty chairs to witness the gleeful encore of “When the Saints Go Marching In”.

The Preservation Hall in New Orleans has no air conditioning, doesn’t serve food or drink, and seats patrons on benches. It sounds a lot like church, actually. But with better music.

(*What the hell is that, by they way? I’ve never understood the pathological need a lot of people seem to feel to leave a concert before it’s finished. I mean, it seems incredibly disrespectful to the performers for one thing, but also, if an extra five minutes in the coat-check line or the parking lot is going to ruin your night, how do you rationalize leaving the house in the first place?)