There is a chord in music that I call “The X-Files Chord”. The X-Files was one of the biggest TV series of the 90s, and also my childhood favorite show.

This show featured an opening theme with a haunting melodic theme, which perfectly captures the super natural theme of this show.

Those 4 notes played as as an arpeggio with space in between each part , have become iconic to this theme.

It hits you straight from the first moment the theme plays, and continues as the background harmony throughout the entire main title.

What is the X-Files Chord

You simply start with a minor triad in root position. Let’s say we use Bb as our key. That gives you a Db and an F, to complete your minor triad. Then you add the note just above the 5th, in this case an Gb. And let’s call that a flat 6.

So what you just created is a Minor (add b6) chord. And if you play these notes as an arpeggio going upwards, one time, and then letting them ring out with some reverb…you have got yourself the iconic X-file chord right there.

Now the main reason for the “spooky and supernatural vibe” is because you combine the emotional mood of a mino triad, with the tension from the semitone interval between the perfect 5th and the added b6.

However, this is important if you are a music theory nerd. I want to point out that technically this chord does not exist. At least if you use traditional chord naming conventions from music theory. However, I like to break the naming rules, when I feel it makes sense. But technically this chord is in fact an Gb Maj 7, in first inversion.

The reason I call it a Minor (add b6), is because when I play the bass with my left hand in octaves, I really hammer home the Bb as the root note of the chord, making it a Bb Minor triad, that I then add a flat 6 on top of. That is how I see it.

But it doesn’t matter what you label the chord as, the true power is using it in your music for adding that spooky, supernatural vibe, similar to the legendary X-File arpeggiated motif.