Defining Tones
Defining tones are notes that determine the quality of the most frequently occurring triads and seventh chords.
Major and minor triads are by far the most frequently occurring triads. These two triads have the root and 5th in common; only the 3rd changes. Thus, the 3rd is the ‘defining tone’ because it determines the quality of the triad, major or minor.
Major and minor triads are by far the most frequently occurring triads. These two triads have the root and 5th in common; only the 3rd changes. Thus, the 3rd is the ‘defining tone’ because it determines the quality of the triad, major or minor.
Major 7ths, dominant 7ths, and minor 7ths are by far the most frequently occurring seventh chords. These three chord types all have the root and 5th in common; only the 3rd and/or 7th chord tones change. Thus, the 3rds and 7ths are the ‘defining tones’ because they determine the quality of the seventh chord, major, dominant or minor.
Note: We are using the standard system of numbered, transposable major scale tones
(ie. major triad = 1, 3, 5 in numbered major scale tones).