You know that feeling when a note sounds so wrong that you check whether your guitar slipped out of tune, your amp died, or your neighbour started drilling — and then you realise, no, the composer did that on purpose, the monster? Congratulations, you've just met a b2 interval, and Ennio Morricone is the villain twirling his moustache.
This little clip is my guitar rendition of Morricone's "The Crisis" — one of those pieces where a single, gorgeously "wrong" note does more heavy lifting than a whole string section. I play through it and point a big flashing arrow at the exact minor second that makes your spine do the thing.
How the b2 interval makes "The Crisis" so unforgettable
A b2 — a minor second — is the smallest step in Western music: two notes just one fret apart, sounding together. Acoustically they're so close that their sound waves "beat" against each other, and your brain reads that roughness as danger, the same way it flinches at a scream or a baby crying. Morricone doesn't hide it or resolve it quickly; he leans a melody note right up against the harmony underneath, holds it, and lets the friction hang in the air. That unresolved rub is the whole mood — dread, grief, tension that never quite exhales. If you want to hear it in isolation, play any note and then the fret right next to it at the same time: that grinding clash is the ingredient. (For the full map of why some pairs of notes fight and others hug, see What are intervals? and the Intervals Cheat Sheet.)
The useful takeaway for your own playing: dissonance isn't a mistake to avoid, it's a spice to place. One well-aimed b2, held just a beat too long, will do more emotional damage than a dozen tasteful consonant chords. Put it on a strong beat, let it ring against a note it "shouldn't" be near, then resolve — or refuse to, like Morricone — and you've weaponised a single semitone. A little harmonic analysis shows you exactly where those clashes live in a piece.
Anyway, if you enjoy me pointing at half-steps and whispering "this one hurts, isn't it beautiful," I have PDF and Guitar Pro files plus a lot more nerdery over on my Patreon — where the notes are wrong on purpose and my conscience is clear.