Editing Thirteenth (section)

==Dominant thirteenth==
{{Image frame|content=<score sound="1">
\new PianoStaff <<
  \new Staff { \key f \major a'1 }
  \new Staff { \key f \major \clef bass <c e bes> }
>>
</score>|caption=Dominant thirteenth chord in [[four-part writing]]{{sfn|Benward|Saker|2009|p=179}}}}

Most commonly, 13th chords serve a [[dominant (music)|dominant]] [[diatonic function|function]] (V<sup>13</sup>),{{sfn|Benward|Saker|2009|p=180}} whether they have the exact intervals of a dominant thirteenth or not. Typically, a dominant chord anticipating a major resolution will feature a natural 13, while a dominant chord anticipating a minor resolution will feature a flat 13.{{sfn|Benward|Saker|2009|p=179}} Since thirteenth chords contain more than four notes, in [[Four-part harmony|four-voice writing]] the root, third, seventh, and thirteenth are most often included,{{sfn|Benward|Saker|2009|p=179}} excluding the fifth, ninth, and eleventh {{Audio|Dominant thirteenth chord on C four voices.mid|Play}}. The third indicates the quality of the chord as major or minor, the seventh is important for the quality as a dominant chord, while the thirteenth is necessary in a thirteenth chord.

[[File:Prelude to the Afternoon of a Faun dominant thirteenth chord.png|thumb|center|400px|Dominant thirteenth chord in [[Claude Debussy]]'s ''[[Prélude à l'après-midi d'un faune]]'' (1894)<ref name="Cope, David 2000 p.6">Cope, David (2000). ''New Directions in Music'', p.6. {{ISBN|1-57766-108-7}}.</ref> {{Audio|Prelude to the Afternoon of a Faun dominant thirteenth chord.mid|Play}}]]

In modern pop and jazz harmony, after the dominant thirteenth, a thirteenth chord (usually notated as ''X<sup>13</sup>'', e.g. C<sup>13</sup>) contains an implied flatted seventh interval. Thus, a C<sup>13</sup> consists of C, E, G, B{{music|flat}}, and A. The underlying harmony during a thirteenth chord is usually [[Mixolydian mode|Mixolydian]] or [[Lydian dominant scale|Lydian dominant]] (see [[chord-scale system]]). A thirteenth chord does not imply the quality of the ninth or eleventh scale degrees. In general, what gives a thirteenth chord its characteristic sound is the dissonance between the flat seventh and the thirteenth, an [[interval (music)|interval]] of a [[major seventh]].

{{Image frame|content=<score sound="1">
\new PianoStaff <<
  \new Staff \fixed c' {
    \omit Score.TimeSignature \time 2/4
    << { e'\glissando c' e'\glissando d' } \\ { f e f e } >>
  }
  \new Staff { \clef bass << { b g b g } \\ { g, c g, c } >> }
  \new Lyrics \lyricmode {
    \markup { V \super 13 } I \bar "||"
    \markup { V \super 13 } \markup { I \super 9 } \bar "||"
  }
>>
</score>|width=300|caption=Voice leading for dominant thirteenth chords in the common practice period.{{sfn|Benward|Saker|2009|pp=183–84}}}}

In the [[common practice period]] the "most common" pitches present in V<sup>13</sup> chord are the root, 3rd, 7th, and 13th; with the 5th, 9th, and 11th "typically omitted".{{sfn|Benward|Saker|2009|pp=183-84}} The 13th is most often in the soprano, or highest voice, and usually resolves down by a 3rd to the tonic I or i. If the V<sup>13</sup> is followed by a I<sup>9</sup> the 13th may resolve to the 9th.{{sfn|Benward|Saker|2009|pp=183–84}}