Study of the Roman theatre of Volterra: Acoustic effects based on the presence of different architectural construction elements

Roman theatres have always been the subject of research studies, from an architectural perspective and archaeology. The border lines between these and other disciplines is always difficult to be established since the interrelation of various expertise is required to achieve a complete knowledge of ancient buildings, especially when documentations and archaeological sources are limited. The present work deals with the acoustic analysis of the Roman theatre of Volterra, located in northern Italy, which has already been the subject of archaeological and architectural studies since its discovery in 1950. Acoustic measurements have been carried out in line with the standard requirements outlined in ISO 3382. After model calibration, the acoustic simulations have been carried out using four specific scenarios, highlighting the contribution that different construction elements can have on the acoustic response of this open-air theatre in comparison with the existing conditions. The results were evaluated assuming that light music (classical quartets, unamplified) and prose are the main functions of the space, as this case was in the past. The simulated results show that the values for the main acoustic parameters are better than the measured values, to be closer to the optimal ranges of the criteria borrowed from studies on enclosed spaces, since there are no criteria for Roman theatres. The good acoustic response of the Roman theatre of Volterra raises new doubts about the function of the vessels that were located under the steps of the cavea, as mentioned by Vitruvius.