Christmas Music Has a Secret Chord That Makes It Sound So Festive

American actors Bing Crosby, Rosemary Clooney, Vera-Ellen, and Danny Kaye sing together, while dressed in fur-trimmed red outfits and standing in front of a stage backrop, in a scene from the film ‘White Christmas,’ directed by Michael Curtiz, 1954. (John Swope/The LIFE Images Collection/Getty Images)

“It’s all in the chords,” says Adam Ragusea. The professor at Mercer University’s Center for Collaborative Journalism is referring to the secret to festive music. It’s a recipe that was perfected by Bing Crosby’s “White Christmas” years ago, and only has been duplicated successfully by just one contemporary artist: Mariah Carey.

For the non-musically minded, a chord is three or more notes played together. (Here’s a famous example from The Beatles.) You might be surprised to learn that many of the most famous songs have fairly simple chord progressions, or series of chords that are built to make a melody. Christmas songs tend to favor a few specific chords—but one stands out among the rest of them: a D-minor 7 flat 5 chord.

Ragusea describes it as “delicious,””spicy,” and warm.” Watch (and listen) to the chord and its place in Christmas music in the video below.

You can read more on Ragusea’s argument here.