The last thing you'd expect in a cover of ABBA's bubbly 1975 pop megahit is a melancholy ballad, but that's exactly what the indie rockers The Rural Alberta Advantage had in store when they came to the Billboard studios armed with acoustic instruments and a yearning, quiet arrangement.

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"I think a key aspect of a really good song is... I'm always listening for the melody first and foremost and a song like "S.O.S." has really great melody," says TRAA singer/guitarist Nils Edenloff of ABBA's track, which reached No. 15 on the Hot 100.

"It goes back to where the band started," he says of of why covering the Swedish quartet's pop harmonies appealed to the Canadian trio, which is rounded out by Amy Cole and Paul Banwatt. "[We had] terrible open mic night that no one would come to, so we had to get a whole bunch of material together -- some ended up being Rural Alberta songs,  but some was filling up the night with covers.

"I like finding the nugget of a song and changing it and making it into something that we would probably write," Edenloff continues, indicating his own songwriting proclivities. And the Rural Alberta Advantage, which formed in 2005, has already seen chart dividends from their efforts. The band managed to hit the Heatseekers chat with 2009 debut "Hometowns." New album, "Departing," is out March 1.

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