Diminished major seventh chord

diminished major seventh
Component intervals from root
major seventh
diminished fifth (tritone)
minor third
root
Tuning
200:240:288:375
Forte no. / Complement
4-18 / 8-18

In music theory, a diminished major seventh chord is a seventh chord composed of a diminished triad and a major seventh.[1] Thus, it is composed of a root note, together with a minor third, a diminished fifth, and a major seventh above the root: (1, ♭3, ♭5, 7). For example, the diminished major seventh chord built on C, commonly written as CoM7, has pitches C–E♭–G♭–B:


{
\override Score.TimeSignature #'stencil = ##f
\relative c' {
   \clef treble 
   \time 4/4
   \key c \major
   <c es ges b>1
} }

Diminished major seventh chords are very dissonant, containing the dissonant intervals of the tritone and the major seventh. They are frequently encountered, especially in jazz, as a diminished seventh chord with an appoggiatura, especially when the melody has the leading note of the given chord: the ability to resolve this dissonance smoothly to a diatonic triad with the same root allows it to be used as a temporary tension before tonic resolution.

The chord can be represented by the integer notation {0, 3, 6, 11}.

Diminished major seventh chord table

Chord Root Minor third Diminished fifth Major seventh
CoM7 C E♭ G♭ B
C♯oM7 C♯ E G B♯ (C)
D♭oM7 D♭ F♭ (E) Adouble flat (G) C
DoM7 D F A♭ C♯
D♯oM7 D♯ F♯ A C double sharp (D)
E♭oM7 E♭ G♭ Bdouble flat (A) D
EoM7 E G B♭ D♯
FoM7 F A♭ C♭ (B) E
F♯oM7 F♯ A C E♯ (F)
G♭oM7 G♭ Bdouble flat (A) Ddouble flat (C) F
GoM7 G B♭ D♭ F♯
G♯oM7 G♯ B D F double sharp (G)
A♭oM7 A♭ C♭ (B) Edouble flat (D) G
AoM7 A C E♭ G♯
A♯oM7 A♯ C♯ E Gdouble sharp (A)
B♭oM7 B♭ D♭ F♭ (E) A
BoM7 B D F A♯

References

  1. ^ Jamini, Deborah. (2005). Harmony And Composition: Basics to Intermediate, p.204. ISBN 978-1-4120-3333-6.