Application of vector intensity techniques for the acoustical characterization of a baroque‐style Italian theater

Results concerning acoustical measurements carried out in the Municipal Theater of Ferrara, built in 1790, are here presented. Recent restoration works replaced the original wooden stage. A model, which describes the enclosed space as a retroactive linear system, has been developed to characterize rooms acoustics. Modifications of the acoustic field, induced by the new stage, were measured by means of the following objective tests: evaluation of the theater transfer function having related input and output, respectively, defined by the free‐field acoustic power of a reference source and the measured power emitted by the same source placed on the stage surface; mapping of isointensity levels over the coupling area between stage and hall (proscenium plane); evaluation of acoustic‐intensity‐based transfer functions over a grid in the proscenium plane. A further description of the theater acoustics was obtained by intensity vector measurements over three parallel grids in the proscenium. Results of this additional characterization are presented as graphic views of acoustic intensity flow lines.