- When analyzing music, each diatonic triad is identified by a Roman numeral.
- The first diatonic triad of a scale uses the Roman numeral for one.
- The second diatonic triad uses the Roman numeral for two.
- This pattern continues.
- In addition, the modern Roman numeral system uses different styles for each triad type.
- Upper-case numerals represent major triads.
- Lower-case numerals represent minor triads.
- Upper-case numerals with a small plus sign represent augmented triads.
- Lower-case numerals with a small circle represent diminished triads.
- Let's apply Roman numerals to the C major scale.
- Since the first triad is major, its numeral is upper-case.
- The second triad is minor. Its numeral is lower-case.
- The third triad's numeral is also lower-case.
- The fourth triad's numeral is upper-case.
- The fifth triad's numeral is also upper-case.
- The sixth triad's numeral is lower-case.
- The seventh triad is diminished. Its numeral is lower-case with a small circle.
- The last triad is the same as the first.
- Next, let's apply Roman numerals to the C natural minor scale.
- Since the first triad is minor, its numeral is lower-case.
- The second triad is diminished. Its numeral is lower-case with a small circle.
- The third triad's numeral is upper-case.
- The fourth triad's numeral is lower-case.
- The fifth triad's numeral is also lower-case.
- The sixth triad's numeral is upper-case.
- The seventh triad's numeral is also upper-case.
- Again, the last triad is the same as the first.
- Next, let's apply Roman numerals to the C harmonic minor scale.
- The third triad is now augmented. Its numeral is upper-case with a small plus sign.
- The fifth triad is now major. Its numeral is upper-case.
- The seventh triad is now diminished. Its numeral is lower-case with a small circle.
- Next, let's apply Roman numerals to the C melodic minor scale.
- The second triad is now minor. Its numeral is lower-case with no circle.
- The fourth triad is now major. Its numeral is upper-case.
- The sixth triad is now diminished. Its numeral is lower-case with a small circle.
- The Roman numeral system can also indicate inversions.
- First inversion is represented by a small 6 after the numeral. This is due to the root being a generic sixth above the bass note.
- Second inversion is represented with both a small 6 and 4. This is due to the root and third being a generic sixth and fourth above the bass note.
- Some theorists use both a 6 and a 3 to represent first inversion.
- While we will use the 6 alone, you should be aware of the other representation.
- Use this chart to reference the Roman numerals for each scale.
- Use this chart to reference the Roman numerals for inversions.