ABSTRACT
This chapter discusses the five triadic formations: major, minor, diminished, augmented, and suspended. It is important to stress that the harmonic and melodic versions of minor are not independent scalar collections; rather, they represent variants or "shades" of the minor scale. The use of key signatures always corresponds to the natural minor form and does not cover the necessary accidentals occurring in the harmonic and melodic forms. Intervals derived from the pitches of other major or minor scales are also diatonic in the context of the respective keys. A triad is the combination of three simultaneously sounding pitches. Tonal music shows a preference for tertian sonorities—called chords, which are built of consecutive major or minor thirds. The four triads—major, minor, diminished, and augmented—explore different combinations of major and minor thirds. The augmented triad is a type of chromatic formation because it contains a non-diatonic pitch.
