This paper focuses on the spectral properties of anterior sibilant fricatives in Northern Peninsular Spanish, and sibilant-merging and non-merging varieties of Basque. Non-merging varieties of Basque have two voiceless anterior sibilant fricatives, characterized as apico-alveolar and lamino-alveolar. In other Basque varieties, however, these two phonemes have merged with varying results. Twenty-four participants divided into four different groups have been studied. One group is a set of monolingual Spanish speakers from north-central Spain, while the remaining three are Basque–Spanish bilingual groups with different sibilant fricative systems in Basque. The goal is to describe the spectral properties of anterior sibilant fricatives and examine the effect of the L1-Basque sibilant system upon L2-Spanish. The Basque varieties chosen are: (i) Azpeitia Basque, where merging in favor of the lamino-alveolar sibilant fricative has occurred; (ii) Lemoa Basque, where the merging in favor of the apico-alveolar sibilant fricative is widespread; and (iii) Goizueta Basque, where no merging has happened. Participants took part in an elicitation task where they produced sentences containing target words with an intervocalic anterior sibilant fricative in Basque and Spanish. Bayesian probability was used for inferential statistics. Speakers of the non-merging Basque variety show the narrowest acoustic dispersion of /s/ in Spanish, as opposed to broader diffusion in the other three groups. Regarding L1 transfer, while the Azpeitia group does not show transfer into Spanish, the Lemoa and Goizueta groups do. Results show that /s/ is more fronted for monolingual Spanish speakers from north-central Spain than the previous literature has reported.

本文重点研究了北半岛西班牙语中前齿擦音的光谱特性，以及巴斯克语的齿擦音合并和非合并变体。巴斯克语的非合并变体有两个清音前齿擦音，其特征是顶端齿槽音和层间齿槽音。然而，在其他巴斯克语变体中，这两个音素合并并产生了不同的结果。对分为四个不同组的二十四名参与者进行了研究。一组是一组来自西班牙中北部的单语西班牙语使用者，而其余三组是巴斯克语-西班牙语双语组，在巴斯克语中具有不同的擦音擦音系统。目的是描述前齿擦音的光谱特性，并检查 L1-巴斯克齿擦音系统对 L2-西班牙语的影响。选择的巴斯克品种是：(i) Azpeitia Basque，其中发生了有利于 lamino-alveolar 擦擦音的合并；(ii) Lemoa 巴斯克语，那里普遍存在有利于顶端牙槽齿擦音的合并；(iii) Goizueta Basque，没有合并发生。参与者参与了一项启发任务，他们在巴斯克语和西班牙语中造出包含目标词的句子，并带有元音间前擦音。贝叶斯概率用于推论统计。非合并巴斯克语种的说话者在西班牙语中表现出最窄的 /s/ 声学扩散，这与其他三组中更广泛的扩散相反。关于 L1 转移，虽然 Azpeitia 组没有显示转移到西班牙语，但 Lemoa 和 Goizueta 组有。