Over the last five years, opera companies across the country have seen more ups and downs than a Rossini aria. But in Buffalo, Nickel City Opera is celebrating five years of high notes.

Its fifth annual production, this weekend at North Tonawanda’s Riviera Theatre, is the comedy “Don Pasquale” by Italian bel canto composer Gaetano Donizetti. Valerian Ruminski, the barrel-voiced bass who runs the company, is giving the production a special, madcap flair.

“We’re going to have a bathtub with a bubble machine. Girls are going to be in the bathtub,” promised Ruminski, who is not known for political correctness. “I told the guy, ‘Let’s pull out all the stops.’ ”

“I want the audience to be shocked. I want them to see something we didn’t do before.”

There are still trends in opera, even after hundreds of years. And Patricia Kiernan Johnson, of the national organization Opera America, suggests that the companies that survive this tough economy are often smaller start-ups, with angles that are unique, confident and, perhaps, offbeat.

“We are seeing a real trend in entrepreneurial spirit,” she said. “A lot of smaller companies are founded on an artist’s vision, finding something to say that couldn’t be said in larger companies. A smaller company can do something more interesting.”

Johnson has noticed small companies that are making a noise in the opera world.

In New York City, the New York City Opera may be struggling but Gotham Chamber Opera is doing well. The upstart company (motto: “Where opera gets intimate”) kicked off with “Il Sogno di Scipione,” an obscure opera by the young Mozart about ancient Rome. Its current production, a contemporary opera, is taking place in the Brooklyn Botanic Gardens.

Baltimore, which suffered the loss in 2009 of the Baltimore Opera, now plays host to several smaller companies including one that performs staged operas in a mansion, accompanied by a piano.

Johnson stressed that the smaller companies are not trying to replace their grander cousins, but want to do something different.

“We’re seeing smaller, more agile companies that say, ‘Look, we’re not going to perform grand opera in a grand house. That’s been done. We’re going to do something more interesting. I have this vision and I’m going to make that happen,’ ” she said.

“A strong artist viewpoint is really important. What’s unique to your organization? What sets you apart from the crowd? There are a lot of options in the entertainment world and out,” she said, citing the Metropolitan Opera’s high-definition simulcasts, which can be seen in Buffalo. “What are you doing that’s unique?”

Rock and ‘Rigoletto’

The answer to that question, in the case of Nickel City Opera, is: “Plenty.”

The Riviera Theatre might seem at first to be a provincial location for an opera company. (One production of “Rigoletto” was briefly interrupted by a rock band pounding at a bar down the block.) But the historic movie palace has its singular charms. Visiting singers have likened it to regional European opera houses.

Ruminski capitalizes on the Riviera’s strengths. He sells popcorn at performances. For several years he has staged the popular Christmas opera “Amahl and the Night Visitors” on Thanksgiving weekend, accompanied by the Mighty Wurlitzer.

He has always had a populist approach. Before founding NCO, he commissioned Buffalo composer Persis Vehar to write songs for him based on the rough-hewn poetry of Charles Bukowski. He has NCO posters drawn by comic book artists and heavy metal artists.

In 2011, the company performed Puccini’s smoldering “Il Tabarro,” about marital jealousy on a ship, at dusk aboard The Sullivans. Johnson, at Opera America, applauds such endeavors.

“That’s another important point, a real authentic relationship with the city you’re in,” she said.

Ruminski plans at some point to stage “Shot!,” an opera by Vehar about the McKinley assassination. Meanwhile, he has been pulling in crowds with proven hits. Rossini’s slapstick “The Barber of Seville” was followed by two dark Verdi dramas, “Rigoletto” and “Il Trovatore.” For “Trovatore,” Ruminski got a bargain on some of the costumes seen in the 1967 movie “Camelot.”

Often, Ruminski has played peripheral roles. His experience showed in how he made the most of them. As the assassin Sparafucile in “Rigoletto,” he skulked about with long black hair, at one point picking his teeth. In “Il Trovatore,” playing the sidekick of the villainous Duke, he grinned nefariously as the Duke announced his evil plans.

In a surprise move, he is starring in this week’s opera as Don Pasquale, a buffoon who decides to wed a young wife, with disastrous consequences. He played the role recently for Hawaii Opera Theatre.

“This for me is a big deal,” he said. “It’s the first time I’ve sung a lead role in one of my own productions.”

Wooing singers to Buffalo

Nickel City Opera’s 2011 induction into Opera America, which requires certain professional criteria, bodes well for the company’s future. Even with those credentials, though, and even with a board of directors and Cheektowaga offices, NCO is not out of the woods.

Ruminski is always on the lookout for operas that are affordable to stage and for deals on costumes and sets. He knows other singers from his work with opera companies around the world – including the Metropolitan Opera, the Canadian Opera Company, the Seattle Opera and companies in Europe – and is able to woo them to Buffalo on a budget.

“Don Pasquale” illustrates his knack for smart spending.

“We have a wonderful soprano from Puerto Rico, a graduate of the Academy of Vocal Arts, singing Norina,” he said, referring to Zulimar Hernandez, playing the attractive widow who is the opera’s leading soprano role. “She just sang this role in Santa Barbara, Calif., two months ago. She sings two Norinas a year. She is a new hot young Norina. I was lucky to get her, in that her agent will let her work for as little money as I’m paying.”

Other singers in “Don Pasquale” include Benjamin Brecher (“He and I were Chautauqua artists together when we were kids,” Ruminski said) and James Wright, who has appeared as one of the Three Kings in “Amahl.” The conductor is Michael Ching, of Opera Memphis. He will be directing a small orchestra – larger than a chamber orchestra, smaller than the BPO. The orchestra will be made up of high-caliber local musicians.

Performances of “Don Pasquale” take place at 8 p.m. Friday and Saturday and 2:30 p.m. Sunday at the Riviera Theater, 67 Webster St., North Tonawanda. Tickets are $24-$59. For information, call 692-2413.