Diatonic Triads & Roman Numerals

Diatonic Triads & Roman Numerals

Roman numeral analysis allow us to apply harmony to any key signature easily. By identifying the step of the scale upon which the chord is built and its quality with roman numerals, we can easily take any chord progression and apply it to any key signature.

Diatonic Triads & Roman Numerals

Roman numerals can be used to identify triads and their function in the scales key signature.

Diatonic Triads & Roman Numerals

The root note of a triad together with the degree of the scale it is built on determines a triad's function within a key.

Diatonic Triads & Roman Numerals

Triads built on the other degree of the scale are auxiliary or supportive triads for the primary triads of the scale.

Diatonic Triads & Roman Numerals

Triads built on the tonic,dominant, and sub-dominant degrees of the scale are primary triads.

Diatonic Triads & Roman Numerals

Triads can be built on any degree of the scale.

Diatonic Triads & Roman Numerals

Two stacked minor thirds create a diminished triad.

Diatonic Triads & Roman Numerals

Upper case roman numerals are generally used to indicate major triads and lower case roman numerals are used to indicate minor triads, and a lower case roman numeral with a degree symbol is used to indicate a diminished triad.

Diatonic Triads & Roman Numerals

Using roman numerals allows for easily recreating chord progressions in any key signature.

Diatonic Triads & Roman Numerals

We can further identify chords though by their diatonic function using roman numerals, now this is a really important and flexible means of analyzing harmony. Among its many advantages is the ease of transposing chord patterns or progressions into different keys.

Diatonic Triads & Roman Numerals

We can say as a rule that triads built on each major key are as follows: 1 chord is always major 2 chord is always minor 3 chord is always minor 4 chord is always major 5 chord is always major 6 chord is always minor 7 chord is always diminished Now that is assuming you don't alter any of the notes in the triad and they all follow the scale tones.