Proscenium
A proscenium (Greek: προσκήνιον, proskḗnion) is the metaphorical vertical plane of space in a theatre, usually surrounded on the top and sides by a physical proscenium arch (whether or not truly "arched") and on the bottom by the stage floor itself, which serves as the frame into which the audience observes from a more or less unified angle the events taking place upon the stage during a theatrical performance. The concept of the fourth wall of the theatre stage space that faces the audience is essentially the same.
For the Atlanta office tower, see The Proscenium.It can be considered as a social construct which divides the actors and their stage-world from the audience which has come to witness it. But since the curtain usually comes down just behind the proscenium arch, it has a physical reality when the curtain is down, hiding the stage from view. The same plane also includes the drop, in traditional theatres of modern times, from the stage level to the "stalls" level of the audience, which was the original meaning of the proscaenium in Roman theatres, where this mini-facade was given more architectural emphasis than is the case in modern theatres. A proscenium stage is structurally different from a thrust stage or an arena stage, as explained below.
Baroque[edit]
While the proscenium arch became an important feature of the traditional European theatre, often becoming very large and elaborate, the original proscaenium front below the stage became plainer.
The introduction of an orchestra pit for musicians during the Baroque era further devalued the proscaenium, bringing the lowest level of the audience's view forward to the front of the pit, where a barrier, typically in wood, screened the pit. What the Romans would have called the proscaenium is, in modern theatres with orchestra pits, normally painted black in order that it does not draw attention.
Confusion around Teatro Olimpico[edit]
In this early modern recreation of a Roman theatre, confusion seems to have been introduced to the use of the revived term in Italian. This emulation of the Roman model extended to refer to the stage area as the "proscenium", and some writers have incorrectly referred to the theatre's scaenae frons as a proscenium, and have even suggested that the central archway in the middle of the scaenae frons was the inspiration for the later development of the full-size proscenium arch.[3] There is no evidence at all for this assumption (indeed, contemporary illustrations of performances at the Teatro Olimpico clearly show that the action took place in front of the scaenae frons and that the actors were rarely framed by the central archway).
The Italian word for a scaenae frons is "proscenio," a major change from Latin. One modern translator explains the wording problem that arises here: "[In this translation from Italian,] we retain the Italian proscenio in the text; it cannot be rendered proscenium for obvious reasons; and there is no English equivalent ... It would also be possible to retain the classical frons scaenae. The Italian "arco scenico" has been translated as "proscenium arch."[4]
In practice, however, the stage in the Teatro Olimpico runs from one edge of the seating area to the other, and only a very limited framing effect is created by the coffered ceiling over the stage and by the partition walls at the corners of the stage where the seating area abuts the floorboards. The result is that in this theatre "the architectural spaces for the audience and the action ... are distinct in treatment yet united by their juxtaposition; no proscenium arch separates them."[5]