Editing Modulation (music) (section)

===Chromatic modulation===
[[File:Chromatic modulation in Bach BWV 300, m. 5-6.png|thumb|right|350px|Chromatic modulation in Bach's ''Du grosser Schmerzensmann'', BWV 300, mm. 5–6<ref name="B&S 245"/> ({{audio|Chromatic modulation in Bach BWV 300, m. 5-6.mid|Play}} with [[half cadence]], {{audio|Chromatic modulation in Bach BWV 300, m. 5-6 with resolution.mid|Play}} with PAC) transitions from F major to D minor through the inflection of C{{music|natural}} to C{{music|sharp}} between the second and third chords. Note that there is no common chord.]]

A chromatic modulation is so named because it occurs at the point of a [[Diatonic and chromatic#Progression|chromatic progression]], one which involves the [[Diatonic and chromatic#Inflection|chromatic inflection]] of one or more notes whose letter name, thus, remains the same though altered through an [[accidental (music)|accidental]].<ref name="B&S 245">Benward and Saker (2003). ''Music: In Theory and Practice'', Vol. I, p. 245. Seventh Edition. {{ISBN|978-0-07-294262-0}}.</ref> Chromatic modulations are often between keys which are ''not'' closely related.<ref name="B&S 245"/> A [[secondary dominant]] or other chromatically [[altered chord]] may be used to lead one voice chromatically up or down on the way to the new key. (In standard four-part [[chorale]]-style writing, this chromatic line will most often be in one voice.) For example, a chromatic modulation from C major to D minor:

:{| class="wikitable" style="text-align:center"
|-
!C major
|IV<br><small>F</small>
|V/ii<br><small>A</small>
|ii<br><small>Dm</small>
|
|-
!D minor
|
|
|i<br><small>Dm</small>
|(...)
|}

In this case, the IV chord in C major (F major) would be spelled F–A–C, the V/ii chord in C major (A major) spelled A–C{{music|sharp}}–E, and the ii chord in C major (D minor), D–F–A. Thus the chromaticism, C–C{{music|sharp}}–D, along the three chords; this could easily be part-written so those notes all occurred in one voice. Despite the common chord (ii in C major or i in D minor), this modulation is chromatic due to this inflection.

The consonant triads for chromatic modulation are {{music|b}}III, {{music|b}}VI, {{music|b}}II, {{music|#}}iv, vii, and {{music|flat}}VII in major, and {{music|natural}}iii, {{music|natural}}vi, {{music|b}}II, {{music|#}}iv, ii, and {{music|natural}}vii in minor.

In the example pictured, a chromatic modulation from F major to D minor:

:{| class="wikitable" style="text-align:center"
|-
!F major
|I<br><small>F</small>
|V<br><small>C</small>
|
|
|
|
|-
!D minor
|
|
|V<br><small>A</small>
|i<br><small>Dm</small>
|iv<br><small>Gm</small>
|V<br><small>A</small>
|}

In this case, the V chord in F major (C major) would be spelled C–E–G, the V in D minor (A major) would be spelled A–C{{music|sharp}}–E. Thus the chromaticism, C–C{{music|sharp}}–D, which is here split between voices but may often easily be part-written so that all three notes occur in one voice.

The combination of chromatic modulation with enharmonic modulation in late [[Romantic music]] led to extremely complex progressions in the music of such composers as [[César Franck]], in which two or three key shifts may occur in the space of a single bar, each phrase ends in a key harmonically remote from its beginning, and great dramatic tension is built while all sense of underlying tonality is temporarily in abeyance. Good examples are to be found in the opening of his [[Symphony in D minor (Franck)|Symphony in D minor]], of which he himself said (see [[q:Special:Search/César Franck|Wikiquote]]) "I dared much, but the next time, you will see, I will dare even more..."; and his ''Trois Chorals'' for organ, especially the first and third of these, indeed fulfill that promise.