From the eerie and sometimes comical aesthetics of her debut album, When We All Fall Asleep, Where Do We Go? it's evident that Billie Eilish and her producer brother, Finneas O'Connell, have an affinity for offbeat sound effects in the music they make together.
Some of these are obvious, like the slurp of an Invisalign removal that begins the album, or the Office dialogue that pokes through in "my strange addiction." But as O'Connell revealed in his recent appearance on The Tonight Show Starring Jimmy Fallon, the siblings have gotten extra creative with some of the unusual noises they use to make beats.
"[Billie] was at the dentist, and they were like, grinding down," O'Connell explained, sharing that he and his sister both wore Invisalign. "Whatever ASMR is, it's the opposite of that...She came home from one of those appointments, and she was like, 'I recorded it.' And I was like, 'great!' And we put it right in 'bury a friend.'"
The whirring noise of a dental drill can be heard across "bury a friend," helping the track achieve its especially ominous sound. But that wasn't all; O'Connell also explained that the hi-hat ticks of "bad guy" are actually another everyday item.
"When you're on a street corner in Australia, you press the button, and then when the 'walk' sign turns on you hear this kind of rhythmic sound that I loved," he said. "It's got, like, a groove."
Lo and behold, that propulsive "groove" helps drive the hook of "bad guy." It makes you wonder what other everyday sounds are hidden across Eilish's music and makes O'Connell's Producer of the Year Grammy all the more well-deserved.
Check out O'Connell's interview with Fallon and listen to the weird sounds below.