C♯ altered scale on guitar

C♯ altered uses C♯, D, E, F, G, A, B. Its Box 1 shape places the root on string 5, fret 4 for a compact altered run.

EFGABDEFGABC♯DEFGEADGBE123
Positions on the neck1 of 5

How it is built

C♯1D♭2E♭3F♭4G♭5A♭6B♭7

Formula 1, ♭2, ♭3, ♭4, ♭5, ♭6, ♭7

How do you play the C♯ altered scale on guitar?

C♯ altered in box 1 runs from fret 0 to fret 3, 16 notes across 6 strings, from E on the low E string at fret 0 up to G on the high e string at fret 3. The root falls on the B string at fret 2.

Every note in this box, string by string
StringFretsNotes
6 (E)0, 1, 3E, F, G
5 (A)0, 2A, B
4 (D)0, 2, 3D, E, F
3 (G)0, 2G, A
2 (B)0, 2, 3B, C♯, D
1 (e)0, 1, 3E, F, G

Box 2 · frets 36

C♯ altered in box 2 runs from fret 3 to fret 6, 13 notes across 6 strings, from G on the low E string at fret 3 up to A on the high e string at fret 5. The root falls on the A string at fret 4 and the G string at fret 6.

Every note in this box, string by string
StringFretsNotes
6 (E)3, 5G, A
5 (A)4, 5C♯, D
4 (D)3, 5F, G
3 (G)4, 6B, C♯
2 (B)3, 5, 6D, E, F
1 (e)3, 5G, A

Box 3 · frets 58

C♯ altered in box 3 runs from fret 5 to fret 8, 14 notes across 6 strings, from A on the low E string at fret 5 up to B on the high e string at fret 7. The root falls on the G string at fret 6.

Every note in this box, string by string
StringFretsNotes
6 (E)5, 7A, B
5 (A)5, 7, 8D, E, F
4 (D)5, 7G, A
3 (G)6, 7C♯, D
2 (B)5, 6, 8E, F, G
1 (e)5, 7A, B

Box 4 · frets 710

C♯ altered in box 4 runs from fret 7 to fret 10, 16 notes across 6 strings, from B on the low E string at fret 7 up to D on the high e string at fret 10. The root falls on the low E string at fret 9 and the high e string at fret 9.

Every note in this box, string by string
StringFretsNotes
6 (E)7, 9, 10B, C♯, D
5 (A)7, 8, 10E, F, G
4 (D)7, 9A, B
3 (G)7, 9, 10D, E, F
2 (B)8, 10G, A
1 (e)7, 9, 10B, C♯, D

Box 5 · frets 912

C♯ altered in box 5 runs from fret 9 to fret 12, 16 notes across 6 strings, from C♯ on the low E string at fret 9 up to E on the high e string at fret 12. The root falls on the low E string at fret 9, the D string at fret 11 and the high e string at fret 9.

Every note in this box, string by string
StringFretsNotes
6 (E)9, 10, 12C♯, D, E
5 (A)10, 12G, A
4 (D)9, 11, 12B, C♯, D
3 (G)9, 10, 12E, F, G
2 (B)10, 12A, B
1 (e)9, 10, 12C♯, D, E

Why it sounds like that

C♯ altered is the seventh mode of D melodic minor. The scale spells 1, ♭2, ♭3, ♭4, ♭5, ♭6, ♭7, with F as the ♭4 and G as the ♭5. Compared with C♯ locrian, the fourth drops from F♯ to F. The pattern H, W, H, W, W, W, W keeps half steps at the start and middle.

When to use it

Use C♯ altered over C♯7♭5 or C♯7♯5 chords in jazz, fusion, and bebop. It fits dominant chords that resolve to F♯ minor or F♯ major. The altered fifths and ninths add tension before a ii–V–I in F♯. Try it over C♯ 7th flat 5 or C♯ 7th sharp 5.

Which position to practise

Practise Box 1 first. It keeps the root on string 5, fret 4 and covers frets 0–3, making the half-step from C♯ to D easy to hear and finger.

Common questions

What notes are in C♯ altered?

C♯ altered contains C♯, D, E, F, G, A, and B. The formula is 1, ♭2, ♭3, ♭4, ♭5, ♭6, ♭7. It is the seventh mode of D melodic minor. It is also spelled D♭ in enharmonic notation for the same sounding root.

Which chords does C♯ altered fit?

C♯ altered fits dominant chords with altered fifths, such as C♯7♭5 and C♯7♯5. It also works over C♯7♭9 and C♯7♯9. These chords typically resolve to F♯ minor or F♯ major.

How does C♯ altered differ from C♯ locrian?

C♯ altered has a flattened fourth (F) while C♯ locrian has a perfect fourth (F♯). The rest of the notes are identical. This single change makes altered sound more dissonant.

What is the step pattern for C♯ altered?

The step pattern is H, W, H, W, W, W, W. Starting on C♯, that gives C♯–D–E–F–G–A–B. The half steps fall between the first two and third and fourth degrees.