## 4 Conclusions  
A complete study of the acoustic behavior of the National Theatre of Zagreb has been conducted using these two approaches: one closer to the standard presentation of the main acoustic parameters in the form of graphs and another considered more innovative and made possible by the employment of the latest generation of equipment during the on-site survey.  
Overall, the acoustics of the National Theatre of Zagreb are suitable for both opera and symphonic music, considering that the reverberation time at mid frequencies is 1.3 s, and the definition varies around 0.5. In addition, the strength has been found to be between 2 dB and 5.3 dB, which is considered an optimal result and is in line with other European opera houses [43], including the Italian opera theatres having an average G value around 4-6 dB in many cases [44].  
The alternative representation of the acoustic behavior of the main hall in the National Theatre of Zagreb is determined by the acoustic maps recorded at different positions across the sitting area. The 360\({}^{\circ}\) video overlay consists of an IR recording at a selected receiver position. This result allows for the visualization of the architectural components contributing to the early and late reflections, along with the visualization of the sound energy intensity at each time frame, as determined by the contour levels [45]. This more advanced methodology can be considered as a practical support for musicians and music lovers who want to find a scientific explanation for seating selection when attending live events.  
Future research studies should focus on comparing these acoustic maps that are realized with a 32-channel spherical microphone array with new measurements that can  
Figure 7: Panoramic view of the acoustic maps at the time of later reflections still with strong energy to be detectable. Microphone positions in the stalls (**A**), first balcony (**D**), second balcony (**F**), and upper gallery (**I**). Time frame from 40 ms to 300 ms. Omnidirectional source on stage.  
be created with a higher number of transducers (i.e., 64) composing the microphone, characterized by the same array typology. Based on predictions, the outcomes are expected to increase the directivity of the virtual microphones and reduce the solid angle between the capsules. This would mean a more accurate detection of soundwaves as they interact with the boundaries of a room before they reach the microphone probe later than the direct sound. Another refinement could involve the graphics of the time frame by highlighting the energy peaks occurring during an IR. In addition, the current system can be further implemented by correlating the contour levels to binaural acoustic parameters that are not described in this paper.  
Conceptualization, L.T.; methodology, L.T.; software, A.B.; validation, A.B. and L.T.; formal analysis, A.B.; investigation, A.B.; resources, L.T.; data curation, A.B.; writing--original draft preparation, A.B.; writing--review and editing, A.B. and L.T.; visualization, A.B.; supervision, L.T.; project administration, L.T.; funding acquisition, L.T. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The authors declare no conflicts of interest.