• Learn about how to map out the neck with chord inversions.
• Create arpeggio-based lines using open strings.
• Understand how to use diminished triads over dominant chords.
How a guitarist uses triads—chords composed of three notes—is very telling when it comes to the big picture in music. A command of triads gives you a foundation for understanding harmony and how the guitar functions. Mastering triads will change you as a player. It takes a little time, but it starts here. The next thing you know, you’ll be managing larger, more complex chords.
For this lesson, let’s focus on the top set of strings, which consists of the 1st, 2nd, and 3rd. It’s vital that you pay attention to every interval inside these triads while you learn them—especially the root, which is your vantage point.
Basic triads contain a root and some form of 3 and 5. What form the 3 and 5 take depends on whether the triad is major (1-3-5), minor (1-b3-5), diminished (1-b3-b5), or augmented (1-3-#5).
There are three basic inversions to learn in each type of triad. Pay close attention to the order of the inversions, as well as where the root appears. This will make the ideas that follow clearer. Ex. 1 shows the inversions for a C major triad; Ex. 2 does the same for a Cm triad.
Dominant 7 chords (1-3-5-b7) contain four notes. Because we’re dealing with three-part harmony, we have to figure out ways to suggest the larger structure using only three notes. One way to do this is to simply play a major triad from the same root, substituting a G major triad (G-B-D) for G7 (G-B-D-F), for example. But because we lose the colorful b7 in the process, this approach can sound bland or generic.
But there is a way to use triads to imply a dominant 7 chord. The trick is to arpeggiate a diminished arpeggio starting on the 3 of the dominant chord. The diminished chord’s ability to invert after every minor third interval makes it very easy to use as well. Ex. 3 illustrates the process using a Bdim triad (B-D-F) over G7. Notice how the Bdim triad contains the top three notes of G7, including the important b7 (F).
As an instructor, I often see students who think they can play through all of the triads. They look so simple right? All I have to do is call a horn key (F, Bb, Ab, Eb) and it’s an instant struggle for most. Because of the guitar’s design, it’s common to just move a shape around in half-steps and assume it has been learned to the fullest extent. This way of learning leaves giant holes and blind spots on the fretboard and in the mind.
To truly learn how something functions, play it through the cycle of fourths. This is not fun, but it gets years of guessing out of the way. Ex. 4 is one of those exercises that you have to make your way through to see what can be seen. If you can manage the cycle of fourths with triads, then cycling with arpeggios, scales, and progressions will follow. (Note: the cycle of fourths is just the cycle of fifths played counter-clockwise).