compositional techniques

A descending fifths sequence is a common compositional technique used by composers from the eighteenth century to expand a simple melodic or harmonic idea. A typical descending fifths sequence is executed when a short melodic phrase is played over a note (or a collection of notes with emphasis on one in particular) in the bass. The next phrase will virtually be an exact copy of the previous phrase and accompanying bassline, except that it will have been transposed an interval of a diatonic fifth downward or a diatonic fourth upward (either direction will result in the same pitches). In other words, the second phrase will begin at the pitches that would result from moving the first phrase down four notes (or up three notes) within the diatonic scale that the music is in. This process often is repeated multiple times in a single section of the music.