The Dominant Chord
We’re exploring the three types of chords that are all you need to see the Big Picture of making music. For the first two chord types (tonic and subdominant), see the past two entries: The Big Picture of Making Music and The Subdominant Chord.
Remember our main point: no matter what you see or hear in notated or recorded music, there are only three types of chords, as they relate to key centers: tonic, dominant and subdominant. These chords set up key centers in our Westernized minds when we hear them.
Let’s look at the dominant chord. What is it, and what’s its purpose in setting up a key center? Time for a metaphor: taking a vacation from home. The tonic chord is like your home. The lovely vacation place you travel to is like the subdominant: it’s great to be there, but you have no illusion about it being your home. Even as your lying on the beach or knocking back that third margarita, a part of you is thinking, “I kind of miss being home (the tonic).”
So when we hear the subdominant (vacation spot), we’re already thinking about getting home. Before too long, we’re on the ship or in the car on way home. That’s the dominant: you’re one step away from being home. When your ear hears a dominant chord, it’s saying “Yipee. We’re almost home. Just one chord away.”
How do we find the dominant chord? There are two that can function as dominant, whether the music you’re hearing is in a minor or major key center. Chords that function as dominants are built on the fifth (V) and seventh (vii) degree of the major or minor scale.
Example: get your guitar and play a G7 followed by a C. The G7 is the V chord in the key center of C major.
There’s another chord in C major that can serve as a dominant, but you might not know it. It’s Bm7b5, the vii in C major. Here’s a pattern for it: X, 3, 2, 3, 2, X. These are fret numbers, reading from left to right, highest pitch E string to low E string.
Play that Bm7b5 chord, then follow it with the C major. See how much like G7 it sounds? As we’ve done with the other chord types, let’s compare the notes of the two dominant types:
G7 has G B D F
Bm7b5 has B D F A
Three out of four notes in common — no wonder they can serve the same function. They’re practically the same chord.
Practical uses? The next time you come across a G7 while playing a tune, try playing Bm7b5 instead. Or, if you’re writing a tune and want a darker feeling than what the G7 provides, use Bm7b5.
Copyright © 2007 Darrin Koltow
This first appeared in the Guitar Noise News - August 1, 2005 newsletter. Reprinted with permission.
February 11th, 2008 at 11:04 pm
Great article Darrin!
Quick question.
You said that aside from G, the Bm7b5 chord is also a dominant in the key of C scale.
I see in lots of classic rock songs they make the they use alot of the bVII majors.
So in the Key of A in some classic rock songs, it is common to hear a G major.
Now I know in those situations, a E major or E7 would be dominant.
But is the bVII or Gmajor also considered dominant in those situations?
Thanks
Dan