The last common borrowed chord we will discuss in this lesson block is the ♭VII chord (“flat seven chord”). While all of the borrowed chord possibilities do get used (including the i, iiº and v), most often you will encounter the minor iv, ♭III, ♭VI, and ♭VII chords borrowed from the parallel minor key.
The ♭VII chord
The ♭VII chord is interesting. It is quite common, but it creates a lot of confusion and is easy to analyze incorrectly. And, sometimes, it causes heated debates. Let's discuss all of this.
Example ♭VII Chord Progressions
In the key of C major, a ♭VII chord would be B♭ (B♭-D-F) or B♭7 (B♭-D-F-A♭) borrowed from the parallel minor scale of C minor. The ♭VII chord appears in chord progressions in many ways.
Often, the ♭VII chord moves back to the I chord: C-B♭-C, or F-B♭-C
Other times it moves to the IV chord: C-B♭-F-C
How the♭VII Chord Works
In many styles of music, use of the viiº chord from the major key is rare. Because the viiº chord is diminished, its flatted fifth can be too dissonant or unstable. It's also doesn't work very well as a rock power chord (“root-5th-root”). Obviously, when things are more difficult to use in music, they don't get used as much as the easy stuff.
Not having an easy-to-use, simple-sounding chord in that seventh spot of the key leaves a big harmonic gap to fill. Welcome ♭VII chord!
The ♭VII chord, being a major triad or dominant 7th chord, is a simpler-sounding chord and fills this harmonic gap in the key.
As a triad, the ♭VII chord is only one note different from the major key's diminished viiº chord: B♭ (B♭-D-F) versus Bº (B-D-F). You get a chord with two of the same notes and lose that dissonant flat-fifth.
When played as a dominant 7th, we get another fun note—the flatted-seventh of the ♭VII chord! (Take a moment to process that.)
In the key of C, using a dominant 7th for the ♭VII chord gives us B♭7 (B♭-D-F-A♭). The A♭ is the flatted-seventh of the B♭7 chord.
This flatted-seventh note of the ♭VII chord often creates that smooth chromatic connection I'm always babbling about. For example, in the progression IV-♭VII-I (Fmaj7-B♭7-Cmaj7), you get the chromatic movement of chord tones: A-A♭-G. A is the third of Fmaj7, A♭ is the flatted-seventh of B♭7, and G is the 5th of Cmaj7. This is the exact same chromatic sound I described to you in the minor iv chord progression IV-iv-I.
If your head is spinning after all of that, it's okay. You can always revisit this when you're ready. This sound isn't going to disappear.
♭VII Chord or IV Chord?
The ♭VII chord can often cause musicians some confusion. If you see the chords C, F and G in a chord progression, your first thought—especially as a beginner—is, “That's I, IV and V in the key of C!” That is true. Those three chords are indeed I, IV and V in the key of C major. But, those chords are also I-♭VII-IV in the key of G major (G, F, C). Which is it? How do you know?
When a song has many chords, it is easier to tell because there's more context. Those other chords can lead you to the right key. When there are fewer chords, it can be ambiguous. Sometimes this leads to heated debates about what key a song is in.
Remember, a key is a tonal center. It is a major or minor scale around which a piece of music revolves. To determine the key, look to where the music resolves, where it comes to rest.
When analyzing music a common mistake is to only look at the chords of a song. Do not overlook the melody. A song is, first and foremost, its melody. The chords support the melody.
To find the key, you can often look to where the melody comes to rest or ends.
Some songs can be ambiguous where a listener can hear it both ways. Just as there are optical illusions like a Necker cube, there are auditory illusions and multiple interpretations and experiences of music.
(There's a lot more to discuss here, and we will circle back to this discussion in future lessons when we thoroughly discuss modes.)
Exercises and Songs
Be sure to check out the exercises and suggested songs for listening and/or playing.
There are a couple of more interesting lessons coming in this lesson block. While some of this may feel over your head right now, soon it won't be. For you to understand and unlock the theory of diatonic chords well, you must be prepared to run into these common exceptions.