Secondary Dominants

Secondary dominants are based on the notion of tonicization. Tonicization is that process where a chord other than tonic is given the emphasis of a tonic function, usually through the use of a secondary dominant. In the case of secondary dominants, the temporary tonicization of a chord other than tonic usually lasts for just a few beats (thus, it's too short to be a real modulation, which we'll study later in the semester).

Secondary dominants emphasize one chord by preceding it with its dominant. The term is "secondary" because the "primary" dominant is simply V7 in the key. Secondary dominants are notated like V7/V and called "five seven of five."

 

  1. Any diatonic major or minor triad may be preceded by its secondary dominant. Notice that this excludes diminished or augmented triads; thus there's no such thing as V/iio or V/viio.
  2. For now, the possibilities are V/x and V7/x and their inversions. Just as V42 resolves to I6 (or i6 in minor), so does V42/x resolve to x6. In theory 4, you'll find out more about other kinds of secondary functions.
  3. Voice leading: secondary dominants resolve just like primary dominants­­just like V7-I (or i). The third goes up, and the seventh goes down. Any of the three V7-I configurations (complete to complete, complete to incomplete, and incomplete to incomplete) is possible. Note carefully that notes with added sharps usually resolve up, while notes with added flats usually resolve down.
  4. Note that V/V or V7/V can progress to I64 (or i64) before moving on to its V, thus: V7/V­­I64­­V­­I.
  5. Secondary dominants thus have a chromatically altered note (or sometimes two; the only secondary dominants which don't have any chromatically altered notes are V7/III and V/VI in minor). Note that V/IV in major is identical to the tonic chord, thus composers add the seventh, creating V7/IV. The chromatically altered note usually functions like a temporary or secondary leading tone. Just like the "regular" 7 intensifies the resolution to 1, this secondary leading tone intensifies motion to the temporary tonic.. By the way, don't confuse chromatic nonchord tones with chromatically altered notes that are part of a secondary dominant.
  6. This all means that you look for chromatically altered notes, see if they're part of a major triad or major-minor seventh, then check to see that it resolves to its "tonic" (root movement up a P4 or down a P5).

     

Writing them: given F: V65/ii, think ii is g. V7 of g is D F# A C. V65 means that the F# should be in the bass.

Hearing them: 1) determine where you hear major-minor seventh chords, 2) determine whether they're diatonic or chromatic, 3) after determining the chromatic chords, listen to where they resolve, 4) listen carefully to the bass motion to determine the inversion. For example: you hear ??­­ii. Identify the ii chord, then listen to how it was approached in the bass. Say the bass moved up a half step: this means that the secondary dominant was V65/ii.

Know the chromatically altered notes:

major: V7/V = #4, V7/IV = b7, V7/ii = #1, V7/vi = #5, V7/iii = #2 and #4.

minor: (Note: for minor, "#6" means altered to be a half-step higher than the 6 indicated by the key signature, like F# in "a" minor; "b7" means the subtonic rather than the leading tone, like G natural in "a" minor); V7/V = #4 and #6, V7/ iv = #3 and b7, V7/VI = b2 and b7, V7/III = b7 and #6, V7/bVII = #6.

Know the roots: V7/V = 2, V7/IV (or iv) = 1, V7/ii = 6, V7/vi (or VI) = 3, V7/iii (or III) = 7, V7/bVII = 4.