Acceptance of synthetic speech in South African languages: A comparative study of Afrikaans, isiZulu, and Sepedi in healthcare contexts

Abstract

While text-to-speech technologies have made significant advances in recent years, questions remain about how synthesised speech is accepted in culturally and linguistically diverse settings such as South Africa. This  study explores how South Africans perceive synthetic speech in comparison to human-recorded speech across three official languages: Afrikaans, isiZulu, and Sepedi, with healthcare as the application context. Using a blind and randomised listening test, 65 participants rated audio prompts across four acceptance metrics: trust, knowledgeability, lik ability, and relatability. Statistical analysis using the Wilcoxon signed-rank test revealed no  significant difference between natural and syn thesised speech perception among Afrikaans  speakers. However, low participation rates prevented meaningful analysis of speech percep tion for isiZulu and Sepedi speakers. When  combining data from all participants, a medium  effect size favouring natural speech was ob served, though this difference was not statistically significant.  These findings suggest that synthetic speech  adapted from natural recordings may be suit able for certain applications in South Africa,  though larger and more linguistically represen tative samples are needed to confirm these results.