A rain of sound from the double elliptical vault inside the monumental stairwell of the Reggia of Caserta

The monumental stairwell of the Reggia of Caserta is characterized by a double elliptical vault to create the effect of a sound rain falling from the ceiling and spread uniformly on the flights of steps. This concept design widely requested by the King, has been achieved in the reality by the construction capabilities of the architect Vanvitelli during the realization of the royal building. Different scholars have been undertaken research studies to find out more details on this effect, but the authors of this paper have been keen to extend the acoustic description of this environment with a creation of a video-overlay that allows to detect the sound energy concentration based on the color scale indicated by the contour levels. The impulse response (IR) recording has been graphically overlapped to a 360° image such that the direction of arrival of the sound wave can be detected. A brief history of the Reggia of Caserta has been introduced as well as the architectural features.