Take the minor pentatonic and add one extra note - the blue note. That's the blues scale. Six notes that carry an entire genre's identity. The blue note is the tritone (b5), and it adds a gritty, expressive kick - like a shot of hot sauce dropped into an otherwise smooth dish.
Minor pentatonic + one note
The blues scale is the minor pentatonic with a b5 (flat five / tritone) inserted between the 4th and 5th degrees. That single addition transforms the sound.
A blues scale
The blue note (b5/Eb) is the secret ingredient
A blues scale - the b5 (Eb/D#) adds that bluesy tension
Semitones from root: 0, 3, 5, 6, 7, 10. The blue note (6 semitones) is a passing tone - you move through it rather than landing on it.
How the blue note works
The blue note creates tension that wants to resolve. It sits right between the 4th and 5th - the two most stable notes after the root. Sliding through it gives that characteristic bent note feeling, even on instruments that can't physically bend.
Typical blue note movement
Pentatonic vs blues
Playing just the root, b3, and 5th (a minor triad) from each scale sounds identical. The blue note is what adds the edge.
The major blues scale
There's also a major blues scale - the major pentatonic plus a blue note between degrees 2 and 3. Less common but equally useful.
C major blues scale
Semitones: 0, 2, 3, 4, 7, 9
C major blues - the b3 (Eb) is the blue note here
Where you'll hear the blues scale
Blues and rock
Guitar solos, bass riffs, vocal melodies. The defining sound of the genre.
Hip-hop and R&B
Melodic hooks, 808 bass patterns, and sampled guitar licks frequently use blues scale intervals.
Jazz
Blues scale over dominant 7th chords is a fundamental jazz improvisation tool.
Pop
Subtle blue notes in vocal melodies add expressiveness without going full blues.
Key takeaway
The blues scale = minor pentatonic + the blue note (b5). Semitones: 0, 3, 5, 6, 7, 10. The blue note is a passing tone that creates gritty tension between the 4th and 5th. There's also a major blues scale (major pentatonic + b3). The blues scale isn't just for blues - it shows up across nearly every popular genre.
Next: now that you know scales, the next step is understanding what a key actually is.
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