Seventh (chord)

In music, the seventh factor of a chord is the note or pitch seven scale degrees above the root or tonal center. When the seventh is the bass note, or lowest note, of the expressed chord, the chord is in third inversion  Play .

Conventionally, the seventh is fourth in importance to the root, fifth, and third, with third inversion being the third strongest inversion and the seventh variably minor or major.

In jazz chords and theory, the seventh is required in a seventh chord. Moreover, most triads that appear in lead sheets or fake books can have sevenths added to them, using the performer's discretion and "ear". For example, if a tune is in the key of C, if there is a G chord, the chord-playing performer will usually "voice" this chord as G7. While in a strict classical music context, the notes of a G7 chord would be "G-B-D-F", in jazz and the fifth of the chord is often omitted and the root is also often omitted if playing in a jazz group, since the bass player will play it. By omitting the root and fifth, this gives the improvising chord-playing musician the option to play other notes.

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