Increase: a lengthening of time; opposed to diminution.
In a contrapuntal composition or one in which melodies are combined, as fugue or canon, augmentation is the device used for prolongation of the principal theme or musical thought and consists of the doubling of the original value of the notes, using whole notes for half notes, half notes for quarter notes, and quarter notes for eighth notes.
The term is chiefly confined to the description of fugal works in which augmentation is but one of the methods employed to give variety and at the same time permit the repetition of the central musical thought or subject.
The changed value of notes brings about an increase in length of musical units, making measures into phrases, phrases into sections and sections into periods, still retaining the theme and by its new setting emphasizing it and increasing the interest of the listener.
It is a method of varying a theme that has been used with good effect by some of the greatest composers. Each employed it in a number of his piano fugues. Handel in the first chorus of Samson and Leo and Cafaro in their Amens.
Abbr. aug., augm.« Back to Dictionary Index