Watched this video from Jazz instruction site Open Studio.
As of 12:27, they discuss “Cush Chords”, a term invented there to describe smooth progressions built through a peculiar interpretation of modal interchange.
The way it works is that they keep the same tonic chord each time and use the same function in the ionian scale from which the mode is taken. So, for instance, going C Dorian from C Major, the chords borrowed are those with the same Roman numerals as the original but based on B♭ Major.
C maj, D min, A min, G maj becomes C maj, C min7, G min, F 7
Now… it sounds to me like part of the “magic” comes from a bit of voice leading. And it’s interesting that there’s a choice of using seventh chords or triads based on… something?
(And one might say that the “interchange” is actually when the original chord appears for just one bar. Otherwise, it’s a modulation. Right?)
Sooo…
Does this correspond to something known, in Scaler world?
What’s the best way to create those progressions without overthinking things?
I believe that this does - Modal Interchange on the MOD page. In the example of Claire de Lune the presenter refers to borrowing chords from the Aeolian mode, which is the natural minor.
I think using either Modal Interchange or possibly Neo-Riemannian modulation will help achieve this.
In the second half of the video the presenter is simply playing a I ii iv V progression across the modes. MDAL INTERCHANGE on the MOD page shows this perfectly.
On the final part of the video that refers to the “Cush Game” I think you can do this easily using the Secondary Scale modulation. The challenge here is knowing the theory that C Aeolian is the vi mode of Eb maj.
I think technically this may be wrong. From my understanding modulation is simply changing key so introducing a borrowed chord is a modulation into a new key, followed by a modulation back to the original key.
That’s the thing, though. In the MOD section, I would need to count the chords from E♭…
From what I understand, MI differs from a modulation in that it doesn’t establish a new tonality. Since it’s short, the borrowed chord is perceived within the original tonality.
