# What kind of cadence is this?

I'm currently learning about periods and there is a question in the book, asking for the closure in m. 4.

The book says it's a half cadence, but it ends on a I (or I64). The only half cadence I see at that point would be the one, ending on the downbeat of m. 4 (I6 - vii°).

Any ideas?

• Just realized that the vii° is actually a V6. Butt Doesnt a half cadence need a dominant triad in root position? Apr 14, 2018 at 11:21

In a comment, you ask whether the half cadence doesn't need a dominant triad in root position. You have one: D F# A.

I 6/4 is a bad analysis of the cadential 6/4. It is not I but V, because this pattern behaves as a (decorated) dominant. The upper parts are appoggiaturas.

In simple terms, I feels like home, and V doesn't. If you were to remove the F# A, extend the G B to the length of a crotchet, and stop the music there, would it feel at all final? No, because of the D in the bass part. This chord still feels like it wants to go somewhere.

Here is a typical example from harmony.org.uk of a good way of writing this progression:

If you are taking a course that requires you to label this progression with I, then you will have to stick it out, but it is misleading and widely criticized.

• Ah, I think I've heard about that before, thanks for pointing it out. I gotta remember that the sustained count too, thanks :) Apr 14, 2018 at 12:33
• FWIW: there's nuance here. In this case, where the 6th and 4th over the bass immediately settle to the 5th and 3rd, writing V 6-5/4-3 is definitely correct. But I had my freshman theory go too far in the other direction: if a cadential 6/4 was interrupted by some extra chords between that chord and the root position V, I was still supposed to write V 6/4, which is ostensibly wrong, as it isn't a 2nd inversion V. So in the case of double appoggiatura, V 6-5/4-3. In the case of extended cadential 6/4, I write a C 6/4. And in the weird case of actual I 6/4 I write it. (Also, passing 6/4.) Apr 14, 2018 at 18:19
• I think it is useful to understand why a cadential I 6/4 works the way it does, pulling down into V. The upper notes above the bass definitely act like non-chord tones. As far as labeling goes, every school is different. Apr 14, 2018 at 23:45

I'd interpret this as an imperfect cadence. Especially due to the dominant pedal crotchet note (a feature used by many Baroque and Classical composers) the chord definitely does not feel finished and wants to move somewhere else.

• I believe the Americans call an imperfect cadence a half cadence, so you are in agreement with the book's term.
– user48353
Apr 16, 2018 at 10:02