Six-four Chords And Plagal Motion

Question 1

What are the four types of 6/4 chords?

Answer 1

Pedal, passing, arpeggiating, and cadential

Question 2

What is a pedal 6/4 chord?

Answer 2

-Bass stays put while the two upper voices move together in parallel motion upwards to an upper neighbor
- use of figured bass symbols shows that these movements take place.
5—6—5
3—4—3
- is more “melodic embellishment,” less “change of melody”

Question 3

What is a passing 6/4 chord?

Answer 3

-is a passing chord to prolong another chord
-commonly found between i6 and i with voice exchange in the outer voices
-interchangeable with vii*6

Question 4

What are arpeggiating 6/4 chords?

Answer 4

-root of chord is played on bottom, then the 6/4 is played on the off-beats
-the only consonant 6/4 chord
-extends a more stable chord
- these chords are not labeled in analysis

Question 5

What are cadential 6/4 chords?

Answer 5

-a I64 chord that resolves to root position V
-has two tones delayed by accented embellishing (NC) tones a step above them.
-aka double suspension depending on what precedes it
- metrically accented
- can connect a ii6 to I by making stepwise motion in soprano possible
-can be anywhere, not just cadences

Question 6

When is a cadential 6/4 treated as a double suspension?

Answer 6

-Soprano: 1–7–1 or 3–2–1 typically
-When it sounds like a suspension
-^3 to ^1 are treated as suspensions

Question 7

When is a cadential 6/4 treated as an accented passing tone?

Answer 7

-when ^3 to ^1 is an accented passing tone, meaning it is not suspended into the V64 chord

Question 8

What is an evaded cadence?

Answer 8

A cadence that is expected, but does not take place.
I.E: V is expected to resolve to I, but putting a passing seventh in the bass (V4/2) resolves it to I6 instead.
- cadential six-four chords are great for evading cadences

Question 9

Why do composers evade cadences?

Answer 9

-To elide two phrases (Sew them together)
-To delay an inevitable cadence to make it more satisfying

Question 10

What is plagal motion?

Answer 10

A motion from the pre-dominant harmony to the tonic harmony.
Aka IV-I motion
IV is embelishing the the I chord

Question 11

Plagal cadence

Answer 11

-Cadence with IV-I
-the amen cadence, used often in sacred texts
-can come after a PAC