17b Discussion - Neapolitan chords (bII6)
Class Discussion
The bII chord.
Another chord that we can borrow is the bII chord from the phrygian mode. This chord is called a Neapolitan 6 chord and has a very smooth resolution to either a I6/4 or a V chord. The Neapolitan 6 chord always acts as a predominant function. When moving to a V chord, do not resolve ra (in the key of C major, Db) to re (D). Instead resolve it down to ti, the third of the V chord.
The Neapolitan 6 chord can also resolve to a viio7/V. In this case, we respell the flat sixth scale degree (Ab in the key of C major) as a sharp fifth scale degree in order to resolve correctly.
Because the root and fifth of a neapolitan chord are tendency tones, we need to double the third.
Another chord that the bII chord can move to is the IVM7(#11) because of very smooth voiceleading.
Class discussion
Standard progressions using the bII
- You can spell this chord enharmonically! We see this in the third mini-example within this example. The Ab in the tenor is changed to a G# in order to make the voice leading make more sense–we go to an A next, so seeing a G# is easier to read.
- A doubled third on a vii dim chord is common because the root and fifth are tendency tones.
- bII6 is going to be the most common version of this chord you see. You can also write it as N6, but we suggest bII6 because that actually informs its function (predominant, just like a regular ii!).
- A root position bII has…problems.
- We’ve introduced rah, which wants to resolve down because it’s a flattened re. So, when it’s followed by a V(7), we either have to have parallel octaves or have a tendency tone resolve in the wrong direction (rah skipping down to ti or going up to re because there’s no doh in V. gross).
- bII6 - iv sounds super cool!
- There’s only a half-step difference which makes voice leading a dream (le down to sol).
- bII6 in the 20th century starts to get weird, functionally. Mahler used it just as a color.
- bII6 is mode mixture: it’s borrowed from Phrygian mode.