Team QUESPA System Submission for the IWSLT 2026 Dialectal and Low-resource Speech Translation Task
Summary
The QUESPA team submitted three unconstrained speech translation (ST) systems for the Quechua to Spanish track of the IWSLT 2026 Evaluation Campaign. Their best-performing system, "contrastive 2," improved upon previous models by integrating a high-performing pre-trained language model for end-to-end ST, avoiding cascading, and incorporating additional Quechua-Collao text. Fine-tuning Microsoft's SpeechT5 model with targeted data augmentation achieved a BLEU score of 27.2 on the official evaluation set. The team also explored prompt-based machine translation using large language models like Gemini, DeepSeek, GPT-5, Claude, and Qwen for the first time. Additionally, they introduced SIDON, an audio enhancement framework. The analysis provides a comparative view across four IWSLT submissions, detailing the impact of synthetic data, external resources, and audio enhancement on fine-tuning performance, underscoring the combined benefits of PLM-based ST, LLM prompting, and ASR enhancement for low-resource speech translation.
Key takeaway
For NLP Engineers developing low-resource speech translation systems, integrating pre-trained language models like SpeechT5 for end-to-end ST is crucial. You should also explore targeted data augmentation with additional text resources and evaluate prompt-based machine translation using advanced LLMs such as Gemini or GPT-5. Additionally, consider implementing audio enhancement frameworks like SIDON to improve input quality, as these complementary approaches significantly boost overall performance in challenging low-resource scenarios.
Key insights
PLM-based speech translation, LLM prompting, and audio enhancement collectively advance low-resource speech translation performance.
Principles
- End-to-end ST benefits from PLMs.
- Data augmentation boosts fine-tuning.
- Audio enhancement improves ST quality.
Method
Fine-tune SpeechT5 with augmented Quechua-Collao text for end-to-end ST. Evaluate prompt-based MT using Gemini, DeepSeek, GPT-5, Claude, and Qwen. Apply SIDON for audio enhancement.
In practice
- Fine-tune SpeechT5 for ST.
- Augment low-resource text data.
- Experiment with LLM prompting.
Topics
- Speech Translation
- Low-Resource Languages
- Pre-trained Language Models
- LLM Prompting
- Data Augmentation
- Audio Enhancement
- IWSLT Evaluation
Best for: Research Scientist, AI Scientist, NLP Engineer
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Editorial summary, takeaway, and curation by AIssential. Original article published by Paper Index on ACL Anthology.