Acoustic analysis of pharyngealization and vowel duration in L2 Arabic by German learners

The present study investigates Arabic vowel production among adult German learners (NNS), addressing a significant gap in the literature. Ten German learners (five males and five females) produced six Modern Standard Arabic (MSA) short and long vowels (/i, i:, u, u:, a, a:/) in both plain and pharyngealized contexts, with ten native Palestinian Arabic speakers (ANS) serving as the comparison group. Pharyngealization was induced by the presence of emphatic consonants (/sˤ, dˤ, tˤ, ðˤ/). The research examined vowel duration, acoustic vowel space, and formant frequencies (F1 and F2) of the target vowels. ANOVA analyses were conducted to examine group differences, while a mixed-effects model was applied to vowel duration to account for speaker variability. F2 lowering was identified as a reliable acoustic correlate of pharyngealization for both groups. The results suggest that NNS successfully maintain pharyngealization in Arabic, further supporting the Speech Learning Model (SLM) predictions. Unlike previous studies, F1 values decreased for pharyngealized vowels in both groups. While NNS speakers preserved vowel length contrasts, they exhibited less vowel backing and fronting than ANS speakers, consistent with prior research. Additionally, NNS exhibited a more compressed vowel space compared to ANS, which may reduce vowel distinctiveness and influence speech intelligibility. The study also discusses pedagogical implications, particularly for Arabic L2 phonetic training, and acknowledges its limitations.