The last few chord substitution articles focused on the V chord in a standard I- IV-V progression. This one focuses on the I chord, and how we can change the chord that everything always resolves to. I will give a few examples of how we can do this in our rhythm playing and our songwriting. Knowing a handful of substitutions will keep our music from getting stale, and our rhythm playing from getting repetitive and boring.
Why would I want to change the I chord, anyway?
Well, you wouldn’t always. Sometimes the I chord, or tonic chord, needs to stay the same because of tradition and style. In a pop music, a simple song/chord structure is needed to appeal to the widest audience. In metal, most chords are power chords (root & 5th) which specify no major or minor tonality, and harmonically, it generally tends to stay within very basic parameters. In genres such as blues, jazz, and singer-songwriter/I-don’t-have-to-label-my-music, dude genres, chord substitutions for the I chord might just set our music apart, or at least keep us awake while playing it.
The I7 for the I
Chances are, you already know a few of these, and didn’t realize. Take a I-IV-V in the key of C:
Now you already know (right?) that most blues cats would never play a C or Cmaj7 for the I chord. They almost always switch it to the swing-approved C7 chord. They do the same for the IV chord too, so our coffeehouse progression above becomes something quite a bit more fun to play:
The vi for the I
This one uses the similarity between the I and the vi chord:
Cmajor7 chord: C E G B
Am7 chord: A C E G
When three of the four notes are the same, that is good enough for me!
The iii for the I
The iii chord is also minor, and has a lot in common with the I. In the key of C, here are the notes:
Cmaj7: C E G B
Em7: E G B D
Again, three notes out of four are the same, so I’d say go for it. It amazes me how different these two chords sound, even though they are so similar. It gives nice ascending motion, and I use this substitution to delay the resolution to the I, like in the progression below:
Other Types of Substitutions
Of course, you can always extend the I chord to make it sound a bit more ambiguous. Instead of the straight major chord acting as the I, try the I6 chord. That is, the major chord with an added 6th tone.
C: C E G
C6: C E G A
The major 6th chord is important because it contains all of the notes in an Am chord (the iv substitution above) and is favored by gospel and R&B guitarists. I like it because it has this unusual ‘sweet’ quality.
The major 9 is a great one to try too. Take your I chord and add a 9 to it. In C, this would be D:
C scale: C D E F G A B C D
You probably already have used this chord before, called a Cadd9. It sounds great on acoustics and 12-strings too.
This substitution goes along with many more which use extensions of the I chord. Some substitutions change the I to a I7, then add extentions, like I9 or I13, or Iflat13:
A word about tone: Many extended chords sound terrible with distortion. Distortion and the even and odd overtones it adds combine in a way to sound like fat Aunt Bess sitting on about 50 piano keys at once. So if you use extended chords, you’d want to do it with a pretty clean sound.
Now hopefully I have given you some things to try when writing songs or playing chords behind someone. With a little bit of work, these shapes will come to you instantly, and you will never be cool with a standard C chord again!
What is your favorite way to alter a chord? Who are some of your favorite, inventive rhythm guitarists?