# Echo Analysis in Iberian Bullfighting Arenas Through Objective Parameters and Acoustic Simulation 1
## 4 Results and Discussion
### Echo Criterion EK in the Study Cases
#### 4.2.3 Results in the Bullring of Las Ventas
\begin{table}
\begin{tabular}{l c c c c c c c c c c} \hline \hline  & \(\mathbf{EK_{speech}}\) & \(\mathbf{EK_{music}}\) & \(\boldsymbol{T_{speech}}\) & \(\boldsymbol{T_{music}}\) & \(\boldsymbol{d_{\text{s+ r}}}\) (m) & \(\boldsymbol{D_{50m}}\) & \(\boldsymbol{ STI}\) & \(\boldsymbol{T_{\text{sm}}}\) (ms) & \\ \hline S1 Ring & & & & & & & & & & \\ Centre & & & & & & & & & & \\ \hline R2 & **1.09** & 1.23 & **181** & 186 & 37.9 & 0.65 & Good & 0.57 & Fair & 124 & Fair \\ R11 & **1.07** & 1.13 & **178** & 181 & 30.3 & 0.51 & Fair & 0.58 & Fair & 163 & Fair \\ R12 & **1.15** & 1.28 & **183** & 187 & 38.1 & 0.62 & Good & 0.57 & Fair & 133 & Fair \\ R16 & **1.02** & 0.99 & **179** & 179 & 29.8 & 0.59 & Good & 0.61 & Good & 137 & Fair \\ \hline S2 Ring & & & & & & & & & & \\ picador line & & & & & & & & & & \\ R17 & **1.11** & 1.45 & **223** & 226 & 60.2 & 0.16 & Poor & 0.48 & Fair & 193 & Fair \\ \hline S3 Music & & & & & & & & & & \\ band & & & & & & & & & & \\ R4 & **1.09** & 1.27 & **346** & 351 & 98.5 & 0.31 & Fair & 0.50 & Fair & 172 & Fair \\ \hline S4 Bugle and & & & & & & & & & & & \\ timpani & & & & & & & & & & \\ R1 & 1.22 & 1.14 & 3691 & 3691 & 64.8 & 0.19 & Poor & 0.51 & Fair & 186 & Fair \\ R2 & 1.12 & 1.04 & 3728 & 146 & 72.6 & 0.23 & Poor & 0.45 & Fair & 182 & Fair \\ R5 & 1.02 & 0.94 & 3491 & 3601 & 88.9 & 0.25 & Poor & 0.46 & Fair & 173 & Fair \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Echo and other acoustic parameters in the Madrid bullring in the audience area. In bold interpreted as an echo. \begin{table}
\begin{tabular}{l c c c c c c c c c c} \hline \hline  & \(\mathbf{EK_{speech}}\) & \(\mathbf{EK_{music}}\) & \(\boldsymbol{T_{speech}}\) & \(\boldsymbol{T_{music}}\) (ms) & \(\boldsymbol{d_{\text{s+ r}}}\) (m) & \(\boldsymbol{D_{50m}}\) & \(\boldsymbol{ STI}\) & \(\boldsymbol{T_{\text{sm}}}\) (ms) & \\ \hline S1 & & & & & & & & & & \\ Ring Centre & & & & & & & & & & \\ \hline E1 & **2.57** & **2.1** & **340** & **176** & 2.1 & 0.91 & Exc. & 0.84 & Exc. & 31 & Exc. \\  & **2.72** & & **142** & & & & & & & \\ E2 & **1.67** & **2.07** & **178** & **147** & 6.9 & 0.78 & Good & 0.69 & Good & 68 & Good \\  & **1.03** & & **310** & & & & & & & \\ E3 & **2.17** & & **95** & & & & & & & \\ E4 & **1.05** & 1.75 & **178** & 100 & 14.9 & 0.54 & Fair & 0.62 & Good & 122 & Fair \\ E4 & 1.31 & 0.98 & 49 & 54 & 22.8 & 0.61 & Good & 0.60 & Good & 123 & Fair \\ E5 & **1.65** & & **93** & & & & & & & \\ E12 & **1.12** & 1.56 & **176** & 98 & 15.0 & 0.39 & Fair & 0.63 & Good & 127 & Fair \\ E6 & 1.46 & 1.19 & 49 & 54 & 22.6 & 0.62 & Good & 0.57 & Fair & 134 & Fair \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Echo and other acoustic parameters in the Madrid bullring with source and receiver both in the ring. In bold interpreted as an echo. By using receivers in this bullring, the acoustic simulation confirms that echoes exist in all four receivers for source S1 in Table 7, both when the bullring is empty and is full of spectators. For the S2-R17 combination, there is only a risk of echo when the bullring is full, and in S3-R4, there is no echo, neither when the bullring is empty nor when the bullring is full. For the three receivers for sound source S4, there is only a risk of echo in the simulation with a full bullring, and, specifically in S4-R5, in neither empty nor full situations is there any risk of echo. This confirms the good agreement between the experimental results and the acoustic simulation results. Regarding the situation when the sound source is located in the centre of the bullring S1 and the receiving microphone is located in Las Ventas arena (Table 8), it can be observed that there is a risk of echo in receivers E1 and E2 for both speech and music. The energy-time and Schroeder curves and the echo parameter values of these two receptors are presented in Figure 15. Figure 15a shows that E1 has a double echo for speech, and E2, Figure 15c, has a triple echo for speech.