Editing Tritone (section)

== Common uses ==
{{more citations needed section|date=January 2017}}

=== Occurrences in diatonic scales ===
The augmented fourth (A4) occurs naturally between the fourth and seventh scale degrees of the [[major scale]] (for example, from F to B in the key of [[C major]]). It is also present in the natural [[minor scale]] as the interval formed between the second and sixth scale degrees (for example, from D to A{{Music|flat}} in the key of [[C minor]]). The melodic minor scale, having two forms, presents a tritone in different locations when ascending and descending (when the scale ascends, the tritone appears between the third and sixth scale degrees and the fourth and seventh scale degrees, and when the scale descends, the tritone appears between the second and sixth scale degrees). [[Supertonic]] chords using the notes from the natural minor mode thus contain a tritone, regardless of inversion. Containing tritones, these scales are [[Anhemitonic scale|tritonic]].

=== Occurrences in chords ===

The dominant seventh chord in root position contains a diminished fifth (tritone) within its pitch construction: it occurs between the third and seventh above the [[root (chord)|root]]. In addition, [[augmented sixth chord]]s, some of which are enharmonic to dominant seventh chords, contain tritones spelled as augmented fourths (for example, the German sixth, from A to D{{music|sharp}} in the key of [[A minor]]); the French sixth chord can be viewed as a superposition of two tritones a major second apart.

The [[diminished triad]] also contains a tritone in its construction, deriving its name from the diminished-fifth interval (i.e. a tritone). The [[half-diminished seventh chord]] contains the same tritone, while the fully [[diminished seventh chord]] is made up of two superposed tritones a minor third apart.

Other chords built on these, such as [[ninth chord]]s, often include tritones (as diminished fifths).

=== Resolution ===
{{thumb|content=<score sound="1">
      \new Staff <<
         \new Voice \relative c' {
             \clef treble \key c \major \time 4/4
             \stemUp b'2 c f e
             }
         \new Voice \relative c' {
             \clef treble \key c \major \time 4/4
             \stemDown f2 e \bar "||" b' c \bar "||"
             }
            >>
</score>}}
In all of the sonorities mentioned above, used in functional harmonic analysis, the tritone pushes towards resolution, generally resolving by [[step (music)|step]] in [[contrary motion]]. This determines the resolution of chords containing tritones.

The augmented fourth resolves outward to a minor or major sixth (the first measure below). The inversion of this, a diminished fifth, resolves inward to a major or minor third (the second measure below). The diminished fifth is often called a tritone in modern [[tonal music|tonal]] theory, but functionally and notationally it can only resolve inwards as a diminished fifth and is therefore not reckoned a tritone—that is, an interval composed of three adjacent whole tones—in mid-[[renaissance]] (early 16th-century) music theory.<ref>{{cite journal |last1=Bent |first1=Margaret |title=Accidentals, Counterpoint and Notation in Aaron's ''Aggiunta'' to the ''Toscanello in Musica'' |journal=Journal of Musicology |date=1994 |volume=12 |issue=3 |pages=306–344 [308] |doi=10.2307/764089|jstor=764089 }}</ref>

=== Other uses ===
The tritone is also one of the defining features of the [[Locrian mode]], being featured between the {{music|scale|1}} and fifth scale degrees.

The half-octave tritone interval is used in the musical/auditory illusion known as the [[tritone paradox]].