# More on Sibilant Devoicing in Spanish Diachrony: An Initial Phonetic Approach
## 4 Discussion
Our findings lead us to the conclusion that [s, z, \(\{\bar{\textsf{J}}\}\)] are more stable and homogeneous in production and perception than [3] and the affricate sibilants, as stated by [PERSON] (1993, p. 210). The aforementioned acoustic features in affricates could pave the way for the preference of unvoiced segments due to the aerodynamic and acoustic restrictions adduced by [PERSON] (2003), [PERSON] and [PERSON] (2010, pp. 39-41), or [PERSON] et al. (2012, pp. 310-12), by ensuring turbulence at the expense of vocal-fold vibration. If there is some level of equivalence or overlap, more efficient options in aerodynamic terms will be produced. From this point of view, the idea of lenition defended by [PERSON] (1997, pp. 494-96) and [PERSON] (2001, p. 107) makes sense: broadly speaking, options in which only turbulence is required can be favoured over those in which turbulence and vocal-fold vibration are needed since it is possible to obtain a similar result, even when no influence of the context may be adduced. However, the increase in duration contradicts a lenition phenomenon. [PERSON] (1993,pp. 222-23) insisted (in line with traditional accounts of historical sibilant devoicing in Spanish) on a strengthening process, though our results seem to be partially coherent with the description of devoicing as a reduction in duration and in the magnitude of articulatory gestures, in accordance with the definition of lenition offered in Bybee and Easterday (2019, p. 271).This reasoning may particularly explain the results for [d\(\overline{3}\)]: ambiguity in production results in perception misparsing and, finally, leads to complete devoicing in production as the final stage in a process of change ([PERSON], 2001; [PERSON], 2004; [PERSON], 1981, 2012). The second relevant issue concerns the perception level. Our data show an evident coincidence between acoustic properties and auditory impression in the Catalan sibilants. In fact, the perception of voicing relies on durational parameters, as [PERSON] (1978), [PERSON] (1995), [PERSON] (2001), and [PERSON] et al. (2012) had pointed out. However, we detected that fraction of unvoiced frames was also involved in the recognition of voicing. As [PERSON] (1995, 1997) and [PERSON] (1981, 2012) remark, listeners seem to rely on more than a single cue to correctly parse the input. Certainly, we only examined two parameters, but it may be equally possible that other acoustic cues are helping to determine voicing adsorption: [PERSON] and [PERSON] (2006, p. 31) mention F1 transitions, the duration of the preceding vowel or F0 of the following vowel, for example. Despite this fact, misparsings are obviously possible and are even more likely when functional load is low ([PERSON] et al., 2013, p. 184): the consideration of [f\(\mathbf{s}\)] as a phoneme is not undisputed, and cases in which [d\(\overline{3}\)] may give rise to minimal pairs are not abundant ([PERSON], 2005, pp. 11-12). Besides, in our experiment, the stimuli were extracted from complete words, thus resulting mostly in sequences with no lexical meaning: in such cases, lexical knowledge could not help in disambiguating the signal. All these considerations may be relevant to our understanding of the sibilant devoicing process in Early Modern Spanish. As commented, the sibilant system in Medieval Spanish was very similar to that in Catalan ([PERSON], 1993; [PERSON], 2006). For this reason, we could attempt to extrapolate the information obtained for Catalan to the sound change in Spanish. In this respect, the first important topic to address is that, as stated by [PERSON] (1993) or [PERSON] (1995, 1997), sibilant devoicing is a phonetically based process. The analysis of Catalan sibilants demonstrates the overlap in the allophonic production of voiced and voiceless sibilant pairs, especially when it comes to voiced sibilant utterances. Only [z] seems to be more resistant to this general tendency. Even duration values indicate this overlap.