# More on Sibilant Devoicing in Spanish Diachrony: An Initial Phonetic Approach
## 3 The Perception Experiment  
### Method  
It has been deemed important to complete this contribution with a preliminary survey of the perception part of the process. As seen before, most of the literature focuses not only on the production aspects of devoicing, but also on the auditory aspects, which are thought to be a key part of the sound change ([PERSON], 2001, 2002; [PERSON], 2004; [PERSON] and [PERSON], 2006; [PERSON], 1981, 2012; [PERSON] and [PERSON], 2014). The results for production raise some interesting questions, especially whether the acoustic cues which have proved successful in the characterization of the degree of voicing (particularly fraction of unvoiced frames and duration) may have a role in the recognition of sibilants as voiced or voiceless ([PERSON], 1995, 1997; [PERSON], 2001, p. 107). With this purpose in mind, we conducted an identification test, whose stimuli were extracted from the recordings in the acoustic experiment. From the utterances analysed we selected the intervocalic sequences which displayed the best acoustic quality (with no background noise, adequate volume and clear acoustic features in the spectrogram). We preferred to use natural stimuli: apart from segmenting the [V_V] sequences from the lexical unit they belonged to in order to make word recognition difficult, there was no other manipulation. Therefore, we chose 8 instances of [s], 10 instances of [z], 8 for [f], 10 for [s], 6 for [s], 14 for [d\(\widehat{z}\)], 10 for [t\(\widehat{t}\)] and 10 for [d\(\widehat{s}\)], which involved 34 cases of fricative sibilants and 40 for affricate sibilants, giving a total of 74 different stimuli. Each stimulus was repeated 3 times and they were presented in random order. Thus, the final number of items was 222.14 The interstimulus silence was 1.5 s. The test was prepared and distributed online with the FOLERPA platform ([PERSON], 2021). It is important to \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Degree of Voicing** & **[s]** & **[z]** & **[l]** & **[s]** & **[fs]** & **[d\(\widehat{z}\)]** & **[t\(\widehat{t}\)]** & **[d\(\widehat{s}\)]** \\ \hline \multicolumn{2}{c}{Voiced} & 1 (1.6\%) & 36 (56.3\%) & 1 (1.6\%) & 29 (46\%) & 5 (5\%) & 12 (18.8\%) & - & 16 (25\%) \\ \hline \multicolumn{2}{c}{Partially Devoiced} & 15 (23.4\%) & 19 (43.8\%) & 28 (43.8\%) & 33 (46.9\%) & 30 (46.9\%) & 50 (78.1\%) & 48 (75\%) & 47 (73.4\%) \\ \hline \multicolumn{2}{c}{Unvoiced} & 48 (75\%) & 9 (14.1\%) & 35 (54.7\%) & 1 (1.6\%) & 29 (45.3\%) & 2 (3.1\%) & 16 (25\%) & 1 (1.6\%) \\ \hline \multirow{3}{*}{Majorcan Catalan} & voiced & - & 11 (45.8\%) & - & 15 (65.2\%) & 4 (16.7\%) & 6 (25\%) & - & 12 (50\%) \\ \cline{2-9}  & partially devoiced & 9 (37.5\%) & 8 (33.3\%) & 17 (70.8\%) & 8 (34.8\%) & 6 (25\%) & 16 (66.7\%) & 18 (75\%) & 12 (50\%) \\ \cline{2-9}  & unvoiced & 15 (62.5\%) & 5 (20.8\%) & 7 (29.2\%) & - & 14 (58.3\%) & 2 (8.3\%) & 6 (25\%) & - \\ \hline \multirow{3}{*}{Girona Central} & voiced & 1 (25\%) & 25 (62.5\%) & 1 (2.5\%) & 14 (35\%) & 1 (2.5\%) & 6 (15\%) & - & 4 (10\%) \\ \cline{2-9}  & partially devoiced & 6 (15\%) & 11 (27.5\%) & 11 (27.5\%) & 25 (62.5\%) & 24 (60\%) & 34 (85\%) & 30 (75\%) & 35 (87.5\%) \\ \cline{2-9}  & unvoiced & 33 (82.5\%) & 4 (10\%) & 28 (70\%) & 1 (2.5\%) & 15 (37.5\%) & - & 10 (25\%) & 1 (2.5\%) \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Number of instances and percentage of occurrence of the three variants determined by [PERSON] (1997) for each sibilant category. remark that cases of [6] entailed some problems: as known, the intervocalic sequences of this sibilant were not in medial position, but in word-initial context. Although in the acoustic experiment we specified that there was no silence between the first vowel and the sibilant, auditory analysis often gave the impression of a cut between them. Consequently, most cases had to be rejected and only 6 utterances could be used. The participants were 26 Catalan-speakers, 14 from Majorca and 12 from Girona, all of them university students.