14a Discussion - Secondary Dominant Chords

Class Discussion

Secondary chords are chords that are borrowed from other keys.

You can substitute the diagonal slash for the words “in the key of”. For example, V/V is the same as saying “V in the key of V”. If you find yourself labeling a chord that doesn’t exist in the key (non-diatonic) it might be a secondary dominant chord!

When a secondary dominant has a chordal seventh, make sure it resolves down to the third of the next chord.

Functional substitution is when a chord is functioning like another chord, (viio and V, ii and IV, vi and I). so we can apply the doubling rules for the other chord. A viio chord functions like a V chord. In this case, you want to double the same tones in either chord: the non-tendency tones. In a V chord, you could

V/V chords are predominant because they replace ii chords.

Class discussion 2022

Secondary Dominant Chords

In a minor key, are i and iv diatonic or chromatic?

• They are diatonic! They show up naturally in minor keys. If we were to have a iv in a major key, that would be a chromatic chord. Any chord that is modified from how it would appear naturally in the major or minor key is chromatic.

A standard progression: I - vi - ii - V - I (in C)

• Remember: fa does not always go to mi. In this progression, if you have F and G in the alto voice for ii and V, fa should go to sol. This is because in circle-of-fifths progressions, thirds always resolve up to the root of the next chord.

Altering ii - V

• The mystery chords are V and I in G major. All we did was alter the key signature for the second two chords. The key signature is a stand-in for adding an accidental (raised third) to ii.

Changing ii to a dominant chord

• In order to get the same effect we got in the last example, we need to add an accidental. Raise the third in ii to get…a V/V! This is called tonicization.
• Tonicization = extending harmony to treat any non-tonic chord as a tonic. Another way to think of this is just us temporarily creating a tonic. Remember, V/V - V movement is really just V - I in the key of V.
• Slashes below the staff = “x of x.” Slashes above the staff = “x over x.” It can be confusing, but try not to mix them up! Remember that Roman numerals label function, whereas chord symbols label the actual notes within a chord.
• Unlike tertiary function chords, secondary dominants replace function, rather than extend/embellish it. I6/4 is always paired with V because it extends dominant function, but V/x is always paired with x because we are temporarily going to x’s key area. One way to remember this is that we are temporarily phasing over to a secondary key.

Do not tonicize ii0 in minor or vii0 ever. There is no diminished key and trying to do this for our part writing in this class is a bad idea. However, in analyses later in the semester you might see a composer do this because the Romantic period was really crazy.

Secondary dominant seventh chords (same progression as before, but with ii7)

• This process is the same as for turning a regular ii into a V/V, but we end up with a V7/V instead!
• How do I tell what inversion a secondary function chord is in?: The inversion figures will always be attached to the Roman numeral to the left of the slash, as seen with V7/V. They go with the “upper” Roman numeral because the “lower” one is just a shorthand for a key in relation to the key we are already in.
• As we’ll see in coming lectures, this process can used to tonicize any major or minor triad.

How do we determine V/V in different keys?

• Literally ask “what is the V of V” and go from there
• Relate V/V to something you’re already very familiar with: ii! In a way, V/V is really just a fancy ii. They share the same root and usually share the same function. The only difference is V/V’s raised third
• If thinking about solfege works better for you, you can use the above point but think about sol and re instead. If you see re and fi together, you’ll know it’s likely a V/V
• These chords are weird and require added accidentals so double-checking (or even triple-checking) them is always a good idea!! Make sure what you ID’d matches up with what you wrote out in the staff.

Further reading