SINGAPORE — There's a blaring sound coming from the demilitarised border between North and South Korea, and it's not from fire the two sides are exchanging. It's coming from 11 giant speakers.

South Korea has been playing propaganda messages over the loudspeakers, which North Korea's state-run news agency is calling "anti-Pyongyang psychological warfare." The North has now threatened war if the speakers aren't shut off by Saturday.

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It's the first time since 2004 that South Korea has used the speakers to blast messages like these across the demilitarized zone (DMZ). Though North Korea has its own speakers on its side of the border, the technology behind the South's is far superior, and their sounds are easily heard.

Those messages promote the life in South Korea, with references to soap operas and stories about North Korean defectors being welcome in the South.

The loudspeakers are also blasting Kpop, and it's a sound that's not totally unfamiliar along the border.

When the North fired a torpedo that sank a warship in 2010, the South responded with the song "Hit Your Heart" by the girl group 4minute.

The lyrics — "baby, you're kidding me? I do what I want and I do it my way" — were a dig at the North's regimented control over its citizens' speech.

North Korea was so incensed by this that it threatened to turn Seoul "into a sea of flames" if it didn't turn down the music.

But it's not like North Korea doesn't have its own flavour of Kpop, albeit one that's a bit more conservative. Looking at this video of the Moranbong Band — whose members were selected by Kim Jong-un himself — you couldn't accuse their practice sessions of being any less rigorous.

Stick around for the 1:50 mark, where they pull off a crazy quick-change costume routine:

According to former North Korean Je Son Lee, mainstream North Korean tastes tended towards the conservative because of their patriarchal society. They frowned upon the skimpy clothes worn by K-poppers across the border.

The music played by the Moranbong Band also sounds a lot more traditional and less electronic in comparison to Southern K-pop because familiar folk tunes were mainstream in North Korea.