Distillation and Pruning for Scalable Self-Supervised Representation-Based Speech Quality Assessment

Benjamin Stahl; Hannes Gamper

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arXiv · 2502.05356

Distillation and Pruning for Scalable Self-Supervised Representation-Based Speech Quality Assessment

Benjamin Stahl·Hannes Gamper

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Abstract

In this paper, we investigate distillation and pruning methods to reduce model size for non-intrusive speech quality assessment based on self-supervised representations. Our experiments build on XLS-R-SQA, a speech quality assessment model using wav2vec 2.0 XLS-R embeddings. We retrain this model on a large compilation of mean opinion score datasets, encompassing over 100,000 labeled clips. For distillation, using this model as a teacher, we generate pseudo-labels on unlabeled degraded speech signals and train student models of varying sizes. For pruning, we use a data-driven strategy. While data-driven pruning performs better at larger model sizes, distillation on unlabeled data is more effective for smaller model sizes. Distillation can halve the gap between the baseline's correlation with ground-truth MOS labels and that of the XLS-R-based teacher model, while reducing model size by two orders of magnitude compared to the teacher model.

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Benjamin Stahl, Hannes Gamper. 2025-02-07. Distillation and Pruning for Scalable Self-Supervised Representation-Based Speech Quality Assessment. https://arxiv.org/abs/2502.05356

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