Skip to content
Preprint

Singlish, Can or Not? Fine-Tuning and Evaluating Zero-Shot TTS for Singapore English

Jul 2026 · 0 citations · 38 references
Engineering

TL;DR

This is the first systematic study of Singlish-accented ZS-TTS, and fine-tuning raises accent similarity on in-domain and out-of-domain speakers for both Chatterbox and CosyVoice 3.

Abstract

Zero-shot text-to-speech (ZS-TTS) achieves near-human quality for standard English, but it copies regional accents poorly. Prompted with a short Singlish utterance, state-of-the-art systems reproduce a speaker's timbre while flattening the accent toward generic English. We investigate whether targeted fine-tuning off-the-shelf ZS-TTS can close the gap for Singapore English (Singlish). We fine-tune two cutting-edge ZS-TTS models, Chatterbox and CosyVoice 3, on 50 Singlish speakers from the IMDA National Speech Corpus. Three speech distributions are evaluated: real recordings against off-the-shelf and fine-tuned generation driven by the same Singlish audio prompts. The evaluation covers four dimensions: naturalness, intelligibility, speaker similarity, and accent similarity. We separate adaptation (in-domain speakers seen during fine-tuning) from consistency (held-out speakers) to test whether accent transfer generalises beyond the training data. Fine-tuning raises accent similarity on in-domain and out-of-domain speakers for both Chatterbox and CosyVoice 3. It moves the generated distribution measurably toward real Singlish, with the gain persisting on held-out speakers. To our knowledge, this is the first systematic study of Singlish-accented TTS.

View source

Similar papers

Preprint Jul 2026

Fr\'echet Distance Loss on Speech Representations for Text-to-Speech Synthesis

Speech Representation Fr'echet Distance loss (SR-FD), a training-time distributional regularizer for tokenizer-free flow-matching autoregressive TTS, is proposed, an intelligibility-improving distributional regularizer for few-step TTS.

Ho-Lam Chung, Kuan-Po Huang, Bo-Ru Lu et al. · 0 citations
Preprint Aug 2026

Domain-Specific Evaluation of Text-to-Speech Systems: A Multi-Metric Benchmarking Study

A reproducible, multi-metric benchmarking framework for systematic evaluation of modern TTS systems through domain-specific analysis, which reveals substantial variation in TTS performance across speech domains, with emotional speech consistently presenting the greatest synthesis challenge.

Ali B. Jafar, Amal Sarmad, Shifa Yousaf et al. · 0 citations
Preprint Aug 2026

Confucius4-TTS: Transcript-Free Cross-Lingual Zero-Shot TTS with a Learnable Speaker Encoder

A multilingual zero-shot TTS system that supports 14 languages and performs both intra-lingual and cross-lingual reference cloning without requiring transcripts of audio prompts, which achieves the best average overall rank in human evaluation among recent open-source and commercial systems.

Hua-Xuan Wang, Hui-Min Wang, Ruiyu Zhang et al. · 0 citations

Models are Zero-Shot Text

Experimental results show that VALL-E outperforms the state-of-the-art zero-shot TTS system in terms of speech naturalness and speaker similarity and could preserve the speaker’s emotion and acoustic environment from the prompt in synthesis.

Unknown authors · 0 citations
Conference Jul 2026

Speech-to-Speech Translation Evaluation: A Systematic Analysis and Multi-Dimensional Metrics

Evaluating speech-to-speech translation (S2ST) systems remains challenging due to the multi-dimensional nature of speech, encompassing semantic accuracy, acoustic quality, and speaker characteristics. Existing approaches rely on either textbased or speech-based metrics, each capturing only partial aspects of translation quality. In this work, we conduct a systematic empirical analysis of S2ST evaluation metrics across multiple language pairs (fr-en, es-en, de-en, hi-en) using SeamlessM4T-v2 translations generated from the FLEURS dataset. We analyze ngram, neural text, and speech-embedding metrics at both corpus and sentence levels. Our analysis shows that text-based metrics are sensitive to linguistic variation but depend on automatic speech recognition (ASR), while speech-based metrics provide more consistent scores yet exhibit limited discriminative ability. Based on these observations, we propose a multi-dimensional evaluation framework that jointly assesses semantic adequacy and acoustic naturalness. The proposed framework improves semantic alignment and achieves strong correlation with speech naturalness across language pairs, enabling more reliable evaluation of S2ST systems.

Lalaram Arya, Mrinmoy Bhattacharjee, S. R. Mahadeva Prasanna · 0 citations
Conference Jul 2026

QMOS: Qwen-Based MOS Prediction for TTS

Text-to-speech systems are improving fast, but measuring how natural they sound still requires expensive human listening tests. Existing automatic methods struggle to generalise well across different datasets. We present QMOS, a MOS prediction framework that extracts hierarchical speech quality features from a frozen Qwen2-Audio large audio language model and combines them with layer-weighted WavLM SSL representations through a learned cross-attention fusion. This design captures both high-level semantic naturalness and lowlevel acoustic distortions in a unified model. On two standard benchmarks, SOMOS and BVCC, QMOS achieves competitive system-level SRCC of 0.923 and 0.921 on SOMOS and BVCC, respectively, while using no system-ID conditioning or listener embeddings. Cross-domain evaluation yields a competitive SRCC of 0.702, suggesting the learned representations generalise across acoustic domains.

Ravi Sastry Kolluru, S. Devarakonda, S. Radhe Shyam Salopanthula et al. · 0 citations

We use cookies to run the site and, with your consent, for analytics and to show ads. See our Cookie Policy.