Effect of Stage Curtain Legs Arrangement on Sound Distribution in Opera Houses

Stage curtain legs are an inseparable element of the theatre stage, but they can appear in many forms and types of construction. The basic function of the legs is the visual separation of the backstage and off stage with a simultaneous possibility for the actors to move around. However, due to their large size and location within the main stage action, the surfaces of the legs have a significant impact on the sound propagation in the room. Most often they are made of textile materials stretched on the frame, which creates a sound-absorbing and reflective acoustic system. The degree of sound absorption and the shape of these surfaces will determine the energy of the sound reflected and transmitted to the audience. The properly selected number of legs and the type of fabric, also have a positive effect on obtaining comparable acoustic conditions in the audience and on stage. The article presents the analysis of the influence of the structure and shape of the stage curtain set layout on the distribution of the sound power parameter at the audience, and also the analysis of the interaction between the stage and orchestra through the example of selected interiors of some opera theaters. The research was carried out on computer models using geometric methods. The results indicate to what extent the type and shape of the legs can affect the transmission of sound from the stage to the audience.