【樂理課堂】和聲：RMlg.hm7 - Chord Progressions

RMlg.hm7 - Learning Music With Ray- Chord ProgressionsA chord progression is a group of chords that travel or progress through a harmonic sequence. A progression can vary in size from two to seven or more chords. They can be either diatonic or chromatic. There are no set rules for chord progressions, although there are some sequences which tend to occur frequently. Diatonic chord progressions contain chords build on only the seven pitches within a given key signature. A triad or seventh chord can be built using each pitch of a major or minor scale as a root for the chord. These chords are given roman numeral labels that correspond to the scale degree within the key that is the root of the chord. In major keys, the diatonic triads and seventh chords are simply constructed by utilizing the root, third, fifth and seventh (in the case of seventh chords) of each scale degree while remaining within the given key signature. In minor keys, the diatonic triads and seventh chords are constructed in almost the same way. However, a slight adjustment needs to be made for two of the chords. The five chord and the seven chord both can act as harmonies that lead to the one chord, so they must possess a leading tone. The natural minor scale contains no leading tone, since the interval between the 7th and 8th scale degrees is a whole step. The harmonic minor scale was created to provide a leading tone when needed for harmonic motion. The key signature of this scale is used when constructing the pitches of the five and seven diatonic chords in minor keys. The key signature of the natural minor scale is used for the construction of all other diatonic minor chords. In addition to diatonic chord progressions, chromatic progressions are also used in music. There are several common methods for utilizing chromatic chord progressions. Mixture is a method in which chords from the parallel minor diatonic sequence are used within a major diatonic progression. .........