Tips for Learning the F# / Gb Blues Scale on Guitar
It is F# minor pentatonic plus one note
Take F# minor pentatonic (F# A B C# E) and slip a C between the 4th (B) and 5th (C#). That single ♭5 — the "blue note" — is the only difference from the pentatonic box.
The blue note is a passing tone
The C♮ sounds tense on its own — use it to pass through, bending or sliding from B up to C#, rather than landing on it. In motion it gives the scale its vocal cry.
The first box at fret 2
Anchor position 1 at fret 2 with the root F# on the low E string — the same shape as F# minor pentatonic, with the C one fret below the C# on each string. A comfortable low-neck box.
Same scale, two spellings
F# blues and Gb blues are the same six notes — guitarists usually read it as F# in sharp keys and Gb when the surrounding music is flat. The fingerings are identical either way.
Target F#, A, and C#
Those three notes spell an F# minor chord and make phrases sound resolved. B, C, and E are colour tones — the C blue note is the spiciest, best saved for tension.
About the F# / Gb Blues Scale
The F# blues scale is six notes — F#, A, B, C, C#, E — the F# minor pentatonic scale with one extra note, the ♭5 (C), added between the 4th and 5th. That added tone is the famous "blue note": it creates the tense, vocal, crying sound that defines blues and rock lead guitar. Written in flats it is the Gb blues scale — the same six notes, two spellings. On the fretboard it sits in the same five box positions as F# minor pentatonic, the first box anchored at fret 2, with the blue note one fret below the 5th on each string.
- 01Notes: F# – A – B – C – C# – E
- 02Scale degrees: 1 – ♭3 – 4 – ♭5 – 5 – ♭7
- 03Built by adding the ♭5 (C) "blue note" to F# minor pentatonic
- 04Six notes — the minor pentatonic plus one chromatic passing tone
- 05Same scale as Gb blues — two spellings, identical fingering
- 06Shares the same five box shapes as F# minor pentatonic
- 07Works over F# minor, F#7, and twelve-bar blues in F#
F# / Gb Blues — note by note
Every blues scale uses the same six-note formula — scale degrees 1, ♭3, 4, ♭5, 5, and ♭7. It is the minor pentatonic with the ♭5 "blue note" added between the 4th and 5th, the chromatic passing tone that gives the blues scale its signature tension and vocal cry.
| Degree | Note | Role | Interval (from root) |
|---|---|---|---|
| 1 | F# / Gb | Root (tonic) | Unison (0 st) |
| ♭3 | A | Minor third | +3 semitones |
| 4 | B | Perfect fourth | +5 semitones |
| ♭5 | C | Blue note (♭5) | +6 semitones |
| 5 | C# / Db | Perfect fifth | +7 semitones |
| ♭7 | E | Minor seventh | +10 semitones |