# More on Sibilant Devoicing in Spanish Diachrony: An Initial Phonetic Approach
## 2 The Acoustic Approach
### Results
#### 2.2.1 Fricative Sibilants
\begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Variables** & \multicolumn{2}{c}{**Type of Sibilant Pair**} \\ \cline{3-5}  & & **Alveolar** & **Alveopalalal** & **Denolalveolar** & **Palatal** \\ \hline \multirow{4}{*}{Voicing} & Duration & F(1, 2) = 89.459, \(p\) = 0.009 & F(1, 2) = 6.922, \(p\) = 0.114 & **F(1, 110) = 14.973,** & **F(1, 2) = 17.292, \(p\) = 0.051 \\ \cline{2-5}  & Intensity & F(1, 2) = 4.092, \(p\) = 0.179 & F(1, 2) = 2.400, \(p\) = 0.252 & F(1, 2) = 1.738, \(p\) = 0.312 & **F(1, 110) = 26.626,** & **F( 0.0001 \\ \cline{2-5}  & Fraction of unvoiced frames & **F(1, 109) = 386.661,** \(p\) = 0.003 & **F(1, 109) = 386.661,** & **F(1, 2) = 32.797, \(p\) < **0.023** & F(1, 2) = 88.786, \(p\) < 0.009 \\ \hline \multirow{4}{*}{Dialect} & Duration & F(1, 14) = 3.249, \(p\) = 0.093 & F(1, 14) = 1.168, \(p\) = 0.298 & F(1, 14) = 1.536, \(p\) = 0.236 & **F(1, 14) = 1.599, \(p\) = 0.227 \\ \cline{2-5}  & Intensity & **F(1, 14) = 5.294, \(p\) < **0.037** & F(1, 14) = 3.681, \(p\) = 0.076 & F(1, 14) = 1.395, \(p\) = 0.257 & F(1, 14) = 4.172, \(p\) = 0.060 \\ \cline{2-5}  & Fraction of unvoiced frames & F(1, 14) = 0.026, \(p\) = 0.873 & **F(1, 14) = 8.152, \(p\) < **0.013** & F(1, 14) = 0.098, \(p\) = 0.759 & **F(1, 14) = 13.440, \(p\) < **0.003** \\ \hline \multirow{4}{*}{Voicing \(\times\) dialect} & Duration & **F(1, 108) = 20.445,** & **F(1, 107) = 4.316, \(p\) < **0.040** & F(1, 110) = 0.113, \(p\) = 0.737 & **F(1, 108) = 8.558, \(p\) < **0.004** \\ \cline{2-5}  & Intensity & F(1, 108) = 1.849, \(p\) = 0.177 & F(1, 107) = 0.387, \(p\) = 0.535 & F(1, 108) = 0.443, \(p\) = 0.507 & **F(1, 110) = 37.320,** \\ \cline{2-5}  & Fraction of unvoiced frames & **F(1, 108) = 5.332, \(p\) < **0.023** & **F(1, 109) = 7.191, \(p\) < **0.008** & F(1, 108) = 1.961, \(p\) = 0.164 & **F(1, 108) = 8.464, \(p\) < **0.004** \\ \hline \multicolumn{5}{l}{**Global cross-category comparison**} \\ \hline \multirow{2}{*}{Phoneme} & Duration & & **F(7, 9) = 51.570, \(p\) < **0.0001** & \\ \cline{2-5}  & Fraction of unvoiced frames & & **F(7, 9) = 82.209, \(p\) < **0.0001** & \\ \hline \multirow{2}{*}{Dialect} & Duration & & **F(1, 14) = 3.440, \(p\) = 0.085 & \\ \cline{2-5}  & Fraction of unvoiced frames & & **F(1, 14) = 2.072, \(p\) = 0.172 & \\ \hline \multirow{2}{*}{
\begin{tabular}{c} Phoneme \(\times\) dialect \\ \end{tabular} } & Duration & & **F(7, 473) = 2.771, \(p\) < **0.008** & \\ \cline{2-5}  & Fraction of unvoiced frames & & **F(7, 473) = 6.640, \(p\) < **0.0001** & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Generalized mixed-effects linear model results for each sibilant pair and in cross-category comparison. Significant results are in bold. display a lower proportion of unvoiced frames (18.18% less; b\({}_{0}=-25.587\), se = 9.957, t = \(-3.678\), \(p<0.002\)) than Girona Central Catalan alveopalalatals. No significant results were detected in duration or intensity values. The speaker affects the model regarding both intensity and fraction of unvoiced frames. There are significant interactions between voicing value and dialect concerning duration (F(1, 107) = 4.316, \(p<0.040\)), apart from fraction of unvoiced frames (F(1, 109) = 7.191, \(p<0.008\)). [] is significantly shorter (14.60 ms less; b\({}_{0}=-14.643\), se = 7.048, t = \(-2.078\), \(p<0.040\)) and has a lower proportion of unvoiced frames (25.58% less; b\({}_{0}=14.812\), se = 5.524, t = 2.682, \(p<0.008\)) in Majorana Catalan. This seems to point to a more voiced realization compared to [] in Girona Central Catalan and, thus, less clear-cut differences between the two alveopalatal phonemes in Majorana Catalan.