My Guitar Notes

C diminished (half-whole) scale

Eight notes alternating half steps and whole steps, beginning with a half step. Because the pattern has a period of three semitones there are only three distinct forms, and any form contains the notes of a diminished seventh chord.

Root
C
Scale
Diminished (half-whole)
Type
symmetric
Notes
C Db Eb E F# G A Bb
Notes in the scale
8
Degree formula
1 b2 b3 3 #4 5 6 b7
Semitones from the root
0 1 3 4 6 7 9 10
Step pattern
H W H W H W H W
Aliases
Octatonic H-W, Half-whole diminished
Key signature of this root
C major / A minor · no sharps or flats
Written use
Named 1 b2 b3 3 #4 5 6 b7. The usual scale over an unaltered dominant seventh chord, especially one that resolves to a minor chord.

Notes and degrees

Each degree of the scale, its note name in this key, and its distance from the root in semitones.

DegreeNoteSemitonesInterval from the root
1C0Perfect unisontonic
b2Db1Minor second
b3Eb3Minor third
3E4Major third
#4F#6Tritone
5G7Perfect fifth
6A9Major sixth
b7Bb10Minor seventh

Positions on the guitar

The five windows below are computed, not copied from a shape chart. The script locates the lowest occurrence of C on each of the five upper strings within the first twelve frets and takes a five-fret window centred on it. Because a scale repeats every twelve frets, these five windows cover the whole neck; the same sequence returns an octave higher. The positions are numbered from the lowest fret upwards, so position 1 is always the window nearest the nut and position 5 the window nearest the twelfth fret.

Position 1

Root on the 2nd string B3 at fret 1. 16 notes of the scale inside this window.

String0123
1st (highest) string E4EF#G
2nd string B3CC#
3rd string G3GAA#
4th string D3D#E
5th string A2AA#C
6th string E2EF#G

Position 2

Root on the 5th string A2 at fret 3. 20 notes of the scale inside this window.

String12345
1st (highest) string E4F#GA
2nd string B3CC#D#E
3rd string G3AA#C
4th string D3D#EF#G
5th string A2A#CC#
6th string E2F#GA

Position 3

Root on the 3rd string G3 at fret 5. 19 notes of the scale inside this window.

String34567
1st (highest) string E4GAA#
2nd string B3D#EF#
3rd string G3A#CC#
4th string D3F#GA
5th string A2CC#D#E
6th string E2GAA#

Position 4

Root on the 6th string E2 at fret 8. 19 notes of the scale inside this window.

String678910
1st (highest) string E4A#CC#
2nd string B3F#GA
3rd string G3C#D#E
4th string D3AA#C
5th string A2D#EF#G
6th string E2A#CC#

Position 5

Root on the 4th string D3 at fret 10. 21 notes of the scale inside this window.

String89101112
1st (highest) string E4CC#D#E
2nd string B3GAA#
3rd string G3D#EF#G
4th string D3A#CC#
5th string A2F#GA
6th string E2CC#D#E

Read the grid as a chord diagram: the top row is the first string. Degrees appear in the notes and degrees table above; a filled cell is a note of the scale, and the shaded cell is the tonic.

Related keys and modes

Related