Overture
Introductory instrumental music.
What it means
The overture is the introductory orchestral piece before a stage work — opera, ballet, play — or before an oratorio. The name comes from the French word for opening. Alongside it stands the concert overture, an independent orchestral piece with no following work, which became a genre of its own in the nineteenth century. The Baroque orchestral suite is also called an overture, because its opening movement represents this type.
Musical use
Historically several types formed: the French overture with a slow dotted introduction and a fugal fast section, the Italian sinfonia in three sections, from which the symphony developed, and, since the late eighteenth century, the overture in sonata-movement form, which often anticipates motifs of the following opera. In the nineteenth century it is partly replaced by a shorter prelude that leads directly into the first scene. The concert overture, in turn, is often laid out programmatically and thus stands at the beginning of the symphonic poem.
Performance practice
Clarify the type, because shaping and tempo relations depend on it; the dotted rhythms of the French overture demand an explicit agreement. Prepare the beginning with particular care, since it gathers the audience and sets the tone of the evening. Plan the intensification toward the close and hold strength in reserve. With overtures containing motifs from the following work, it is worthwhile to know these references and make them audible. Check the effect in the room, because openings react sensitively to acoustics.
Bear in mind that overtures are often played as independent concert pieces although they lead toward a stage work: in concert the ending then needs different treatment than in the theatre, where it passes into the first scene. Clarify this before rehearsal. In concert performances, clarify whether the opera's ending or a specially composed concert ending is played. Examples of overtures with themes from the opera are Weber's Der Freischütz overture and Wagner's overture to Tannhäuser.
Check whether a concert version of the ending exists, if the piece is played without the following stage work.