# More on Sibilant Devoicing in Spanish Diachrony: An Initial Phonetic Approach
## 2 The Acoustic Approach
### Results
#### 2.2.1 Fricative Sibilants  
Results from fricative sibilants will be addressed first. Descriptive data concerning duration, intensity and fraction of unvoiced frames are presented in Table 4. Overall, voiceless fricatives have a longer duration, greater intensity and a higher proportion of unvoiced frames than their voiced counterparts. This general tendency is observed in both dialects examined. It is interesting to note that the results for voiced fricatives display more variability than those for voiceless fricatives, particularly in the fraction of unvoiced frames, but also in duration in the case of [3], which is the most variable segment in this aspect. This suggests more heterogeneous realizations regarding these parameters. [2] shows more variation in the unvoiced frames portion not only globally, but also if inspected by dialect. Inspection of the alveolar pair reveals that duration and fraction of unvoiced frames depend on the voicing value (F(1, 2) = 89.459, \(p\) < 0.009 and F(1, 2) = 181.648, \(p\) < 0.003). [s] is significantly longer (36.03 ms. on average; b\({}_{0}\) = 48.143, se = 4.255, t = 11.316, \(p\) < 0.001) and has a higher portion of unvoiced frames (54.71% more; b\({}_{0}\) = 63.717, se = 4.904, t = 12.993, \(p\) < 0.0001) than [2]. There are no significant differences between these consonants concerning intensity. However, dialect does condition intensity (F(1, 14) = 5.294, \(p\) < 0.037): in Majorcan Catalan, alveolar sibilants display lower intensity (b\({}_{0}\) = \(-\)5.742, se = 2.218, t = \(-\)2.589, \(p\) = 0.019) than in Girona Central Catalan. Neither word nor speaker show an effect on the results, except for intensity as a main effect (se = 6.431, \(Z\) = 2.421, \(p\) < 0.015). When we examine the interaction between voicing value and dialect, we obtain important information: it is statistically relevant when it comes to duration (F(1, 108) = 20.445, \(p\) < 0.0001) and the fraction of unvoiced frames (F(1, 108) = 5.352, \(p\) < 0.023). In Majorcan Catalan, [s] is significantly shorter than in Girona Central Catalan (21.24 ms less; b\({}_{0}\) = \(-\)24.211, se = 5.354, t = \(-\)4.522, \(p\) < 0.0001) and it also displays a lower proportion of unvoiced frames (7.8% less; b\({}_{0}\) = \(-\)17.997, se = 7.779, t = \(-\)2.313, \(p\) < 0.023). Furthermore, Majorcan Catalan [z] \begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{2}{c}{**Sibilant Type**} & \multicolumn{2}{c}{**Girona Central Catalan**} & \multicolumn{2}{c}{**Majorcan Catalan**} \\ \hline \multirow{2}{*}{Alveolar sibilants} & voiceless [s] & 2 & 2 \\  & voiced [z] & 2 & 2 \\ \hline \multirow{2}{*}{Alveopalatal sibilants} & voiceless [f] & 2 & 2 \\  & voiced [s] & 2 & 2 \\ \hline \multirow{2}{*}{Dentoalveolar sibilants} & voiceless [f] & 2 & 2 \\  & voiced [d\(\overline{z}\)] & 2 & 2 \\ \hline \multirow{2}{*}{Palatal sibilants} & voiceless [f] & 2 & 2 \\  & voiced [d\(\overline{z}\)] & 2 & 2 \\ \hline \multicolumn{2}{c}{Total per speaker:} & \multicolumn{2}{c}{\(16\times 2\) = 32} \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Number of cases in the corpus for each sibilant, and number of utterances read by each speaker. has a significantly higher proportion of unvoiced frames (10.19% more) and less intensity (5.74 dB less) than Girona Central Catalan [\(z\)]. Alveopalatals only display significant differences between voiced and voiceless category in the fraction of unvoiced frames (F(1, 109) = 386.661, \(p\) < 0.0001), which is statistically higher in [\(J\)] (54.30% more; \(\text{p}_{0}\) = 46.091, se = 3.358, t = 13.969, \(p\) < 0.0001) than in [\(z\)]. Dialect also affects this parameter (F(1, 14) = 8.152, \(p\) < 0.013): Major