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Canadian experimental rock band Angine de Poitrine performs during a concert part of the Nuits Botanique music festival in Brussels on May 28.JOHN THYS/AFP/Getty Images

Quebec’s costumed indie microtonal duo Angine de Poitrine – which is enjoying a sudden and meteoric rise in popularity – has been moved to the main stage for this month’s Ottawa Bluesfest.

When the Bluesfest lineup was announced in late February, the two-person band from Saguenay was booked to play a side stage along the Ottawa River with room for about 6,000 people.

But since then, the band has been riding a wave of virality. In early February, Seattle radio station KEXP published a 27-minute set by the masked and polka-dotted pair on YouTube.

The Globe and Mail reported in April that the video had been viewed seven million times. That tally will soon surpass 17 million and their tour dates are mostly sold out.

Fans jammed downtown Montreal last weekend to see the band perform a free show for the city’s jazz festival, which organizers described as the biggest crowd they had seen since Stevie Wonder played to 200,000 people in 2009. No official crowd counts were released as it was a free concert without tickets.

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Aerial shots showed the Montreal crowd spanning several blocks. A jazz festival organizer called it a historic evening on stage, pointing out that the band played for about 2,000 people at the same event a year earlier.

Bluesfest spokesperson Joe Reilly said the festival had already been in talks with the band about moving to the main stage before seeing the size of the Montreal crowd.

He said the main stage area can accommodate tens of thousands of concert goers.

“You always book hoping a couple of artists might suddenly do some kind of break for you, but I don’t know if we’ve ever experienced this with such an indie band before,” he said. “It’s kind of astonishing.”

Moving to the main stage will make for an unusual lineup.

Angine de Poitrine will play on Friday, July 17, ahead of Sheryl Crow and country singer Ella Langley.

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The two-person band from Saguenay was originally booked to play a side stage show with room for about 6,000 people before being moved to the festival's main stage.HO/The Canadian Press

Mr. Reilly said that night has the strongest ticket sales of the nine-day event. He said Ella Langley is also experiencing a “buzz” of popularity that is likely also driving demand.

“She’s probably the buzziest country artist in North America right now,” he said. “Is it the top country artist in North America or is it the top buzz band with their zany stage appearance and amazing performances that are doing it? Who knows?”

Ella Langley currently has the No. 1 and No. 3 songs on Billboard’s Hot 100 chart.

It will be a hectic stretch for Angine de Poitrine. On July 14, they open for Jack White at the RBC Ampitheatre before making their headline Toronto debut at the Mod Club later that night. They also play the Mod Club on the 15th and 18th.

On July 19, they play the Hillside Festival in Guelph, which announced Thursday that it is also moving the band to its main stage as the closing act.

Angine de Poitrine’s albums, – 2024’s Vol. 1 and this year’s Vol. II – have both placed on Billboard charts. The duo accepted the Billboard Canada Global Breakthrough Award in June.

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True to form, the anonymous musicians accepted the award without speaking.

Their stage personas are “space-time voyagers” Klek and Khn de Poitrine. Other than saying “Angine de Poitrine” and adding a few noises here and there, they are entirely instrumental. The band’s name translates to angina chest pain, but rhymes nicely in French.

One member plays the drums and the other plays a double-neck microtonal guitar, meaning it is both a bass guitar and an electric guitar, with more frets – and therefore more notes – than a regular guitar.

The band also relies heavily on loops and effect pedals, creating a unique mix of rock, jazz and dance music.

They are assiduous about keeping their real identities private, though they have given a few interviews without cameras in their own voices. The pair have been playing music together in Saguenay since they were teenagers.

In an April interview with Montreal culture website cultmtl.com, Khn, the guitarist, said the project was a culmination of inside jokes that allowed them to play more shows. Klek, the drummer, said they’ve come to appreciate the anonymity.

“There’s a comfort to feeling, ‘Oh, I’m this on stage,’ but after that, I’m a normal person,” he said.

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