The Cadential 6/4

Hi there everyone! This is Dr. Meier here with a video for you on the cadential 6-4. What is the cadential 6-4? The cadential 6-4 is an expansion of the 5 chord, usually at a cadence, which adds weight and breadth to the cadence through the suspension of the 4th above scale degree 5 in the bass. Below you can see a perfect authentic cadence in C major. Here's what it sounds like. On the downbeat of beat 3 there's a chord with a 6th and a 4th above the bass. The 6th moves down by step to the 5th and the 4th resolves to the 3rd to create a root position 5-3 chord with the bass. This whole configuration is what I mean when I say cadential 6-4. The setup and the resolution are both important. Notice that beat 3 is spelled like a tonic triad in first inversion, but since we want to be accurate in our analysis of function, we label it as one roman numeral with two figured bass symbols. Again, it's not a 1-6-4 because it is an expansion of 5. We will never label it 1-6-4 ever. Let's talk about some important characteristics of the cadential 6-4. This figure will always occur on a strong beat and move to a weak beat. This means in 4-4 the cadential 6-4 will probably begin on beat 3 and sometimes beat 1, but never beat 2 or beat 4. The 4th in the cadential 6-4 will always resolve down by step to the 3rd just like in 4th species counterpoint. The 4th acts as a suspension, which must be treated carefully because it's a dissonance. The 6th of the cadential 6-4 does not have such strict movement criteria and instead may move to the 5th or to the 7th of the chord. The cadential 6-4 has two common ending chords, that of the triad on 5 which we've seen, or the 7th chord on 5. Both occur frequently in tonal music. Below here I have two cadential 6-4s ending in 7th chords. The left has four voices and on the right there are three voices. Here's an example of a basic cadential 6-4 in real music. Listen to this example from Mozart's Piano Sonata K. 331 and see if you can spot the cadential 6-4s. The example has two phrases and two cadences, a perfect spot for a cadential 6-4. The outer framework of the first phrase is 1-2-6-5, achieved by a tonic prolongation involving 5-6 and a predominant. The cadential 6-4 occurs at the end of the phrase on 5 at the half cadence. You can see how the 6th and the 4th above the bass move down by step to 5 and 3. Moving to the next phrase, it begins the same way as the first phrase, with the outer framework taking us all the way through our harmonic cycle from 1-2-6 to 5, resolving to 1 in a perfect authentic cadence at the end of the phrase. The cadential 6-4 here has the root of the 7 chord doubled in the tenor voice, which moves to 7 in addition to the other expected members of the expansion. It's common to see the addition of the 7th before an authentic cadence. Listen to the example again and follow with the analysis. Here's an example of a less common usage of the cadential 6-4. Listen to this Beethoven sonata and see if you can spot the figure. In F major, this 8-measure phrase has the outer framework of 1-5-7-1. The cadential 6-4s that occur in the 2nd and 4th measures do not resolve to their tonic goal, but rather act as an expansion of the tonic framework in the first half of the phrase. So you see, the cadential 6-4 doesn't have to appear solely at cadences, but that's generally where you'll find it. Listen once more to how these cadential 6-4s do not resolve to the tonic, but rather expand it. Let's see if you can construct some cadential 6-4s of your own. Pause the video and spell out and properly voice lead all the tones in a cadential 6-4 in F minor that moves to a triad, and in B major that moves to a 7th chord. Notice there are no key signatures for you, so you should add some accidentals. You should have something that looks similar to these. Your notes may be in different voices, but they should all be present in your answer. In F minor, the 5-6-4 is spelled C-F-Ab-C and moves to 5-5-3, spelled C-E-natural-G-C. In B major, the 5-6-4 is spelled F-sharp-D-sharp-F-sharp-B and moves to F-sharp-C-sharp-E-A-sharp. Make sure that all of your chords are spelled correctly and all the voices are led correctly, especially the 4th, which must always resolve down by step. In this video, we learned that the cadential 6-4 is an embellishment of 5 that is most frequently found at the cadence. Even though the cadential 6-4 is spelled like a tonic triad, it's actually an expansion of 5 and will be labeled as such. A few characteristics of the cadential 6-4 indicate that it will always occur on a strong beat because of the suspension of the 4th, and the cadential 6-4 may move to 5 or 5-7, both of which are common. That's all for now, thanks for watching!