The Great Northern Irish Pipers Club was in the midst of a discussion when one of the members picked up his bagpipes and started playing a spirited jig.

Rude? Brazen? At the very least, out of order?

Actually, it was business as usual at the monthly meetings, which inevitably turn into jam sessions.

The club is part of a small but dedicated cadre of musicians who will celebrate St. Patrick’s Day in what they insist is true Irish tradition: playing uilleann bagpipes, the smaller, quieter and more versatile cousin of the better known Highland bagpipes. But unlike the Highland pipes, which are rooted in Scotland, these are 100 percent Irish.

“There’s nothing wrong” with the Highland pipes, said Tom Klein, one of the more accomplished uilleann pipe players in the region. “But the fact is that there is a real, bona fide Irish instrument — the uilleann pipes — that captures the heart and soul of Irish traditional music like the Scottish pipes never will.”

Nonetheless, it’s the Highland pipes that get all the attention. Especially on St. Patrick’s Day.

“Now it’s become part of the Irish-American experience to have a Highland pipe band come marching through your bar,” Klein said. “Don’t get me wrong: I love the Highland pipes, and I have many, many friends who play them. But they are essentially Scottish bands, wearing Scottish gear, playing Scottish instruments and performing some Irish — and a good deal of Scottish — music.”

Uilleann pipers don’t march — the instrument is played while seated — they don’t wear flashy outfits that lend themselves to ribald jokes, and their pipes aren’t nearly as loud; in fact, they often are played to accompany other instruments or even singers. But even though the history of uilleann pipes in Ireland predates the arrival of the Highland pipes by centuries, it’s the marching bagpipers who have become synonymous with St. Patrick’s Day in this country.

“It started with the Irish immigrants and their police and fire bands,” said Mick Bauer, the club’s president. “Then it just sort of took off.”

The uilleann pipes (pronounced “ILL-un,” although they also are called Irish pipes or, occasionally, union pipes) became popular here only in the mid-1990s, when an Irish step-dancing show barnstormed the country.

“There are two eras of the Irish pipes,” said Eamonn Tunney, who grew up in Dublin and now lives in St. Paul. “There’s pre-‘Riverdance’ and post-‘Riverdance.’ ”

Still, the pipes have struggled to find mainstream acceptance — not just among listeners, but among prospective players, many of whom are intimidated by them.

“The Irish uilleann pipes are one of the world’s most complicated and difficult to play instruments,” Klein said.

The club varies in membership from 15 to 20, Bauer said, with another 40 or so who are described as “Internet members.” “I think some people sign up just out of morbid curiosity,” he said with a laugh.

The pipes are not for the casual music buff. Of the seven players who turned out for a recent jam session, three were classically trained musicians and a fourth makes his living as a composer. Most of them practice an hour a day.

Each club member has a story about how they became involved with the instrument. For some it was the sound, for others the challenge of mastering it. And then there are those who aren’t entirely sure.

“You don’t pick the Irish pipes,” said John Ingman, who also plays tuba in the St. Cloud Symphony Orchestra. “The pipes pick you.”

Very different instruments

Although they both are classified as bagpipes, the uilleann and Highland pipes have many more differences than similarities. Each has three drones (pipes that play a continuous note) and a chanter (the pipe with finger holes on which the melody is played) that are powered by air squeezed out of a bag, but that’s the end of the synonymity.

“Very few of the skills transfer,” said Ryan Behnke, who plays both types. “Even the fingering on the chanters is different.”

The chanters on the Highland pipes can play only one octave, while the Irish pipes play two. In addition, the Irish pipes have three extra pipes, called regulators, with keys on them that enable the playing of harmonies and chords. It’s “played dry,” meaning that musicians use a bellows to inflate it rather than their mouths.

Highland pipes, which trace their history back to the military, were designed to be played outdoors and in unison. The uilleann pipes, on the other hand, are an indoor instrument with a softer, mellower sound. Uniformity is not important; on the contrary, the pipers often compare themselves to jazz musicians.

“Other than when you’re accompanying dancers, if you play a song exactly the same way twice, you’ll be laughed off the stage,” Bauer said. “Improvisation and variation are very highly sought after. Even a group of pipers playing together will sound slightly different” from one another.

The pipes range in price from $1,200 to the sky’s the limit. A good pipe maker — and there are only a handful of them in the world — builds everything to order by hand and produces just one set of pipes a month.

“I waited five years to get my set,” said Patrick Maun. “And I was lucky. I could have waited up to 20 years.”

Other pipers prefer older sets. “It’s like wine — it gets better with age,” said Tunney, who plays on a set he describes as “pre-1906. That’s when it arrived in the United States. I don’t know when it was actually made, but I do know that it’s really old.”

All the pipers agree that once a person is hooked on uilleann pipes, you can’t get away from them. Scott Aksamit played Highland pipes for five years before transitioning to the Irish pipes 18 months ago. He regrets not having made the conversion earlier.

“Now I focus just on this,” he said. “I love it. I wish I had started 20 years ago, but at least I should have another 20 years to perfect it.”