12. Napolitan 6th, Picardy 3rd & Faurean cadence

This is the 12th episode of music theory in 5 minutes and we will see 6 special chords and chord progressions, that in special contexts can wear some special names.

A list of 6 maybe a bit long for a 5 minutes format, so I'll might have to split this in two videos, so in this first part we will focus on the first 3 chords and chord progressions on the list.

Number 1: the napolitan 6th

We kind of saw it already in the previous episode about substitutions. It is more or less the same thing than the tritonic substitution.
When you are making an authentic cadence, which is a progression that goes from a chord of the Vth degree to the chord of the Ist degree, you can then replace the chord of the Vth degree by the chord that is a triton (or three tones) above or below. In either major or minor tonality you should end up with a chord that is between your Ist and your IInd degree, so we can note that bII.
Then, if this new chord 's lowest note is its third, then we call it a napolitan 6th

Let's see an example to see that clearer, and why we call that a 6th.
In C major (again, that's all the white keys on a piano keyboard) the Vth degree would be G major, and the Ist degree should be C major.
Then if you transpose this Vth degree 3 tones above, it becomes a Db major chord (and it's the same if you transpose the G major 3 tones below).
Now we need to put the third of this Db major at the bass. So I'll move this Db up an octave, so the third F becomes the lowest note.

This combinaison of notes, Db, F and Ab will still be a Db chord, but this configuration can be seen as a F with a third Ab and a sixth Db. So this could be a F 6th chord, which is the first inversion of Db major.

That's why it's called a napolitan sixth. Napolitan because replacing the Vth degree by a bII in this way was used a lot by the napolitan school, which gathered a lot of huge composers of Italian opera in the 18th century.
The major chord on this bII call also be used in root position or in second inversion (that means with the root note at the bass or with the fifth at the bass) we can then call it "napolitan chord"

The Napolitan chord, or the Napolitan 6th, is also often used to go to the Vth degree, and then to the Ist degree.
Then it occupies the function of a subdominant (degree II or IV) and it is also as a subdominant that it is described most of the time).

Number 2: picardy third

This is also called the picardy cadence. It happens only in minor tonalities, or in some modes where the Ist degree is a minor chord.

The picardy cadence is an alteration of a conclusive cadence that appears at the end of a whole section, or at the end of a music. It is when you replace the last Ist degree, that then should be minor, by a major chord. You do that by raising the third of this chord by a semi-ton. That's why we call it the "picardy third". The origin of "picardy" in the name is unknown but we often give the credit to Jean-Jacques Rousseau who defines it in his dictionary of music. That's where he said that this way of concluding a music survived longer un religious music, and more in picardy, a northern region of France, where there was music in a lot of cathedrals and churches.

This picardy third gives a feel of "happy ending" at the end of song that is in minor. And was even perceived as being more conclusive.
It could occur in an authentic cadence, but also in a plagal cadence, which is conclusive as well.

Number 3: faurean cadence (Gabriel Fauré)

The faurean cadence is a special form of the half-cadence which is a musical sentence that finishes on the degree V.

The half cadence is not a conclusive cadence and it is often prepared with a Ist degree chord, so we have a progression of I - V, the exact opposite of an authentic cadence, and that emphasizes the feeling of suspension that this cadence provide.
So in C major, this half cadence would be CM to GM.

Now the faurean cadence is a particular version of that, and it has the name of Gabriel Fauré because he used this a lot.
Basically, you replace this Ist degree by a IVth degree, you play it in its dominant 7 form, and you put the 5th of that chord at the bass.

Let's break it down.

So we're still in C major, so we will lend on a G major chord, which is our Vth degree. And just before we put a chord of IVth degree, that's F.
Then we'll make it a dominant 7th chord, So that's the root note F, a major 3rd A, a perfect 5th C, and a minor 7th Eb.

Then if I put the 5th at the bass, the C is now the note that will support the whole chord. That makes it feel a tiny bit more like the C chord we had in the regular half cadence. In theory that makes it a little bit more effective.

So this is what we call a Faurean cadence.

Now you can notice that the note Eb flat here, is not supposed to be in our scale. Well, this is kind of a borrowing the melodic minor scale that we saw in a previous episode.
The melodic minor scale is like the major scale except the 3rd is minor, the 3rd note is flat. so we can borrow the C melodic minor, where the 3rd note E is flat, that allow us to build this F dominant 7 chord.

In C minor though, this is less of a borrowing as we are already in a minor tonality.

Anyways, a half cadence that goes IV - V with dominant 7 on the IV, that's a Faurean cadence.

And this will conclude the first part of this episode. Next time we'll see 3 other special chords and chord progressions.