Suspended chord

Dominant seventh with added 4th, also written as a slash chord.^[1] Play (help·info)

A suspended chord ('sus chord) is a chord in which the third is omitted, usually with either a perfect fourth ( play (help·info)) or a major second ( play (help·info)) added, although the fourth is far more common. The lack of a minor or a major third in the chord creates an open sound, which can suggest a minor or a major tonality.

The term is borrowed from the contrapuntal technique of suspension, where a note from a previous chord is carried over to the next chord, and then resolved down to the third or tonic, suspending a note from the previous chord. However, in modern usage, the term concerns only the notes played at a given time; in a suspended chord the added tone does not necessarily resolve, and is not necessarily "prepared" (i.e., held over) from the prior chord.

Suspended chords are commonly found in folk music and popular music. An example can be found in the piece "One Short Day", part of the Wicked musical by Stephen Schwartz, which starts with a descending arpeggio of a suspended chord. In rock, the verse of the Who song "Pinball Wizard" is a sequence of suspended fourth chords resolving to their major counterparts (Bsus4-B Asus4-A etc). In pop/synth-pop, Erasure's "A Little Respect" employs major to suspended changes in much of the song's harmonization. Another example with major to suspended progression is Johnny Thunders' "You Can't Put Your Arms Around a Memory".

A jazz sus chord is a dominant seventh chord with an added fourth, Gsus, and may be written as a slash chord, F/G, and even Dm7/G so as to show its function in ii-V-I progressions.^[1][2] Jazz from the 1940s on may retain the 3rd along with the 4th, though this makes the chord more dissonant, especially depending on whether the voicing is close or open and whether the fourth is below or above the third.^[1]

Contrast with sixth chord.

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