Opera isn’t always high art. Sometimes it’s just plain, cheap fun. “Attila,” Verdi’s ninth opera, is an example; it’s full of oompahs and bluster and delightful high-wire acts for the voice. Its plot is negligible, but moments such as Odabella’s aria in the prologue, when the soprano hauls off and belts out a high note like there’s no tomorrow, are hard to resist.

In concert, as the Washington Concert Opera offered it at George Washington University’s Lisner Auditorium on Friday night, it’s calculated to bring out the inner sports fan in any opera lover — which is a perfectly appropriate response to a majority of 19th-century Italian opera.

Friday’s performance wouldn’t have been half so much fun without a conductor like WCO’s Antony Walker. Walker exudes delight: He always seems to be enjoying himself, throwing himself into his readings, which is a trait that all too often gets lost in today’s music world. He smooths over the occasional bumps of this pickup orchestra, and his assistant conductor and chorus master, Bruce Stasyna, has done an impressive job honing the abilities of the chorus, to judge from the precision with which it negotiated entrances and exits and offstage passages.

I often say early Verdi isn’t done more because it’s so hard to find a soprano who can sing roles such as Odabella in “Attila” or Abigaille in “Nabucco” (coming to the Washington National Opera in April). WCO fielded Brenda Harris, and it could have done much worse. Harris brought to mind Christa Ludwig’s lament that a singer’s art peaks just as her physical abilities are beginning to wane. Harris is a woman of a certain age, and there were hints of dryness and wobble around the corners of her sound, but she sure knows how to use her voice.

She also gets Verdi’s style: Not only did she nail tricky coloratura passages, she shaped her lines so that she delivered the most at climactic moments. Some might focus on her flaws, and there were a few, but in this repertory, she’s ahead of the pack, including singers much better known than she is.

“Attila,” though, is supposed to be the bass’s show. It was a frequent vehicle for Samuel Ramey; when the Metropolitan Opera mounted the work in 2010, it offered Ildar Abdrazakov, who didn’t quite cut it. It’s curious that the Met didn’t turn to John Relyea, who is practically its house bass, and who made a respectable showing with WCO on Friday. But Relyea is more reliable than exciting.

It was nice to hear that he is continuing to grow into his voice, sounding richer and fuller than he has on some previous Met outings (the small size of the theater didn’t hurt). Yet my inner sports fan missed the drama. There’s a sameness to his singing, and he often lost focus at what should have been climaxes. To be effective in this repertory, it helps to be a little cheap.

What you don’t want is obedience: I’d rather see a singer go for broke, and break, than pad safely along the tightrope. The baritone Jason Stearns, as Ezio, did break for a moment, but he wasn’t exactly going for broke when it happened. My enjoyment of his steely, clarion sound was tempered by the viscosity of his legato, the way that he slurred in connecting one note and another.

Ezio gets the most explicitly political message of “Attila”: “Conquer the world, but leave me Italy!” You can just imagine the audience erupting in cheers and catcalls, but the mood wasn’t quite there in this iteration.

Arthur Espiritu was miscast as the tenor lead, Floresto, his voice too soft, gentle and tasteful for this not very tasteful music. James Flora made a stronger showing in the smaller part of Uldino. And Soloman Howard confronted Relyea in the bass-against-bass face-off of the bishop Leone and Attila, offering a young, warm, soft sound.

Everyone had flagged a bit by the final trio, one of the opera’s showpieces, but by then the pace was moving along so fast that one hardly had time to be disappointed. Soon enough, Odabella had stabbed Attila, and the opera was over, probably not to be exhumed again in this city for some time. And flaws or not, the evening added up to a vivid reminder of what WCO offers Washington: repertory we don’t otherwise get, singers we might not otherwise hear and opera with a sense of fun.