## 4 Results and Discussion  
Figures 9 and 10 report the results of several monaural parameters obtained with the two sound sources on the stage for the theatre in Scenario 1, Scenario 2, and Scenario 3. First, the effect of occupancy on the acoustical parameters was investigated. The reverberation time was analyzed, and it appears that Eszterhaza Opera House, with its great volume and highly reflective materials, favors high reverberation times at mid-frequency. Slightly lower differences between unoccupied and occupied theatre appeared for EDT and T10 possibly as a consequence of the big air volume and the contribution of unchanged early reflections, whereas in Scenario 3, the theatre was less reverberant than the others due to smaller air volume. The acoustic characteristic of the Opera House in terms of music perception is important since [PERSON]'s symphonies and chamber music was listened by Prince [PERSON]. As can be seen from the graphs, the center time spans from 88 ms (with dressing rooms on the stage) to 97 ms (without the audience) at 1 kHz, while the parameter C80 assumes values between 1.5 dB (without the audience) and 2.3 dB (with dressing rooms on the stage) at mid-frequencies and therefore, the presence of the audience and the dressing rooms on the stage cause small changes in terms of music perception. The parameter C80 shows that the theatre dated 1784 had a better desirable condition for musical performances. Figure 9: Averaged values of the simulated acoustic parameters (Early Decay Time (EDT) and T10) for the theatre in Scenario 1 (empty theatre), Scenario 2 (with the audience), and Scenario 3 (3D model reconstructed according to the plan dated 1784 in unoccupied condition). The clarity C50 in all configurations results about 0.2 dB at 1000 Hz, which corresponds to quite good conditions for speech listening, as found in other theatres [31]. The analysis then considered the sound strength (G), and the results show that the dressing rooms on the stage have no effect over the sound strength values in Scenario 1. Conversely, the presence of the audience in the hall significantly changes the results of the sound strength. Figure 11 reports the maps of the T30, C80, and STI in Scenario 1 (unoccupied condition). The maps give the following indications: the reverberation time is around 1.55 s in the Royal box in front of the stage and seems that, in this area, the T30 remains almost uniform as if the sound was perfectly diffused. The reverberation time values vary from around 1.59 s in the stalls near the Prince's box to around 1.68 s near the stage. Figure 10: Averaged values of the simulated acoustic parameters (**a**) Ts, (**b**) C80, (**c**) C50, and (**d**) G for the theatre in Scenario 1 (empty theatre), Scenario 2 (with the audience), and Scenario 3 (3D model reconstructed according to the plan dated 1784 in unoccupied condition). At the frequency of 1 kHz, the parameter C80 results around 1.65 dB in the Royal box, confirming the uniformity of the perception in all the positions reserved for the prince. However, the situation in the stalls and galleries differs significantly, in fact, it is interesting to notice that the positions in the right  
Figure 11: Color maps at 1 kHz of the T30 (**a**), C80 (**b**), and Speech Transmission Index (STI) (**c**) in unoccupied condition and with asymmetrical positions of the sound sources A and B on the stage. side of audience area and the left galley have clarity values around 0 dB, whereas in the other parts of the hall the values are above 1.6 dB. Finally, in order to assess speech intelligibility, the Speech Transmission Index (STI) was considered. The parameter results are in the good range (the values span from 0.6 to 0.7). Anyway, in the stalls and galleries, focalization phenomenon seems to be forming but it is due to the different position of the sound sources A and B on the stage.