Major and Minor Triads
All of the chords in this book are called tertian chords. Tertian chords are essentially stacked thirds. Nothing epitomizes stacked thirds more than the basic triad. A triad has three notes; hence, the prefix
Why spell out a C minor triad with an E-flat rather than a D-sharp?
An E-flat and a D-sharp sound the same on a piano. However, an E-flat must be written if you are to create a minor third interval. The interval from C to D-sharp is an augmented second. D-sharp and E-flat are enharmonic partners.
As you might guess, the major triad contains a major third. If you're counting half steps or semitones, the major third is five steps away from the root. In C major, these steps are C (1), C-sharp (2), D (3), D-sharp (4), and E (5). As you know from Chapter 2, the relationship between a C and an E is a major third. The minor third contains only four half steps. This means that the third scale degree is flatted. In C major, the steps are C (1), C-sharp (2), D (3), and E-flat (4).
FIGURE 6-1 shows you a C major and a C minor triad. Again, the only difference between these chords is the third. You will see an E-natural in the C major triad and an E-flat in the C minor triad.
FIGURE 6-1: C Major and C Minor Triads
Since these chords contain three notes, they can be written with three different roots. When C is in the bottom, as in FIGURE 6-1, the chords are in root position. When the third is in the bottom, these chords are in first position. When the fifth is in the bottom, these chords are written in second position. In general terms, first and second positions are called inversions.
In baroque music, inversions would be notated using figured bass. Figured bass is a numeral system used to tell musicians how to voice chords in relationship to a bass line. Although this method of notation is still widely used in music theory classes, it has little application to blues, rock, and pop music.
FIGURE 6-2 shows you major and minor triadic inversions in C major and C minor. Questions will inevitably arise, such as how do you know what inversion(s) to use, and when. It all depends on voice leading and musical context. For more on this topic, see the “Chord Voicings” section in Chapter 12.
FIGURE 6-2: Major and Minor Triadic Inversions