“There’s one completely crazy instrument that I recorded,” Herdís Stefánsdóttir told /Film. “I had never heard it played before. It’s the contrabass clarinet.” On the woodwind spectrum, contrabass clarinets are an octave lower than bass clarinets, and two octaves lower than traditional soprano clarinets. The composer points out that the unique instrument “goes so many octaves lower” than those you’d normally hear, and notes that its central to the theme that accompanies the four strangers who appear at the doorstep of the film’s much put-upon central family.
“In the ‘Four Horseman’ cue, the bass drone you hear in the beginning is the contrabass clarinet, and it creates all these weird squeaks and noises and harmonics,” Stefánsdóttir said. The track, which you can listen to on Back Lot Music’s YouTube channel, starts with a buzzing noise that sounds a bit like a helicopter or the wings of an insect. Both images fit perfectly with the film’s apocalyptic themes of potential “plagues” unleashed upon the modern world.