Paul Simon should have removed his sunglasses sooner at the New Orleans Jazz and Heritage Festival.

Late Friday afternoon, he strode onto the main Acura Stage in shades, a hat and a long-sleeved, light-blue shirt adorned with a button depicting his late friend Allen Toussaint — the same kind of button worn by Elvis Costello on Thursday at the Gentilly Stage.

Simon and his sprawling, multinational band eased in with “The Boy in the Bubble” and “50 Ways to Leave Your Lover,” classics from his back catalog.

And then he spoke those most dreaded of words, especially in a festival setting: “We’re going to play a new song for you now.”

Simon has a new album coming out in June, “Stranger to Stranger.” Showcasing some of it for many thousands of potential purchasers makes sense.

But selecting “The Werewolf” as the introduction to that album made a hard sell even harder. The word on the new album is that it is as much about sonic textures as about songs. Indeed, “The Werewolf” came across as a sort of spoken-word narrative over odd sound effects, largely absent melody or rhythm. It was...not good.

This wasn’t rhymin’ Simon; this was experimental Simon. And, it seemed, uncomfortable Simon.

The Jazz Fest date was the first show of what is to be a lengthy tour. Testing the band and new material for the first time in front of such a large crowd cannot be easy, even for someone with his decades of experience. And it showed.

After “The Werewolf,” he was uncertain about whether to even attempt the next number on the set list. “Have we got this song?” he asked the band. “Can we do it?”

Duing the 2010 Jazz Fest, Simon stepped up and saved the day when partner Art Garfunkel’s voice went missing. When Simon performed at the intimate Le Petit Theatre du Vieux Carre in December as a benefit for a charity Toussaint co-founded, he was loose, playful, energized and confident. He and his ace band cruised through his greatest hits in front of the 300 or so ticket holders fortunate enough to be there. He seemed to be having as much fun as anyone.

That wasn’t the case at Jazz Fest on Friday, especially during the first 30, tentative minutes, despite some lovely moments in “Mother and Child Reunion” and the ballad “Duncan.” The crowd, sizable but not nearly as big as those for Pearl Jam and the Red Hot Chili Peppers during Jazz Fest’s first weekend, thinned noticeably.

Finally, he took off the sunglasses for a light-on-its-feet “Me and Julio Down by the Schoolyard.” Looking the audience directly in the eyes seemed to help. Dancing and singing broke out on the field, at long last.

Simon cracked a smile, directing his musicians in a bit of faux-beat-boxing. A big tenor saxophone solo lit up “Still Crazy After All These Years.” Zydeco rubboard and accordion came into play, always a plus and always a source of joy.

But the set was hit and miss from there on in. Simon encouraged musicians to take surprising twists, as when the pianist embarked on a solo that would have been more at home in the Jazz Tent. Such segments of the show will likely play better when his tour visits more sonically pristine theaters.

Simon’s finger snaps accompanied the a cappella opening of “Diamonds on the Soles of Her Shoes”; a drum solo concluded the arrangement. By the time they arrived at “You Can Call Me Al,” he had warmed to the task; he played an enthusiastic air flute solo.

The big video screens flanking the Acura Stage usually enhance the experience, enabling even the far-flung corners of the field to get a sense of what is happening onstage. Additionally, the screens can provide intimate views of the musicians’ hands and faces during solos, as they did with the Tedeschi Trucks Band on Thursday.

But the screens’ advantages were squandered during Simon’s set. The camera remained focused on him, even if he wasn’t doing anything while another member of the band engaged in an epic, intricate solo.

I would have liked to watch the bassist during the robust, finger-picked solo that concluded “You Can Call Me Al.” Instead, we got a view of Simon watching the bassist off-screen.

The encores opened with another track from “Stranger to Stranger,” “Wristband,” which chronicles the protagonist musician’s frustration at being locked out of his own show without the proper credential to be readmitted. In the final verse, he tries to spin the saga into a larger metaphor of the haves and have-nots. The word “wristband” is repeated a whole lot. The song can cut two ways: It is either brilliantly simple and clever, or completely trivial and trite.

Many, many more worthy songs from his repertoire might have been substituted for “The Werewolf” and “Wristband.” The timeless “Graceland,” which was absent from the show, springs to mind.

“Father and Daughter,” which followed “Wristband,” was an affecting, sweet bit of emotional and parental honesty. “We’re not there yet, but it’s getting late,” Simon said by way of introduction to “Late in the Evening.”

Another stone-cold classic from his deep catalog, “The Boxer,” seemingly brought the show to a conclusion. The audience started to pack up; apparently, the camera operator did as well.

But after a long pause, Simon returned to the stage alone. As he unspooled a hushed, lovely, solo “The Sound of Silence,” the big screens continued to show advertisements for the festival’s sponsors.

In his final moments at Jazz Fest, Simon was invisible to all but those closest to the stage, the last awkward moment in a set that had more than its share of them.

Follow Keith Spera on Twitter, @Keith Spera.