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Common-tone diminished seventh chord

diminished seventh
Component intervals from root
diminished seventh
diminished fifth (tritone)
minor third
root
Tuning
125:150:180:216
Forte no. / Complement
4–28 / 8–28

The diminished seventh chord is commonly used in the harmony of both Western classical music and also in jazz and popular music of the twentieth and twenty-first centuries. Classical composers of the eighteenth and nineteenth centuries imaginatively exploited the chord's dramatic and expressive potential. (See below).

A diminished seventh chord is a four note chord that comprises a diminished triad plus the interval of a diminished seventh (alternatively regarded enharmonically as a major sixth) above the root. Thus it is (1, 3, 5, double flat7), or enharmonically (1, 3, 5, 6), of any minor scale; for example, C diminished-seventh would be (C, E, G, Bdouble flat), or enharmonically (C, E, G, A). It occurs as a leading-tone seventh chord in harmonic minor and can be represented by the integer notation {0, 3, 6, 9}.


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