AD-Mamba: Architecture-Complementary Knowledge Distillation for Efficient and Robust Audio Classification

Abstract

Recent advancements in large-scale audio classification have been primarily driven by Transformer-based architectures due to their strong capacity in modeling long-range dependencies. However, their inherent quadratic complexity limits scalability and efficiency, especially when processing long or sparsely informative audio streams. Mamba, a recently proposed state space model (SSM), offers a promising alternative by enabling efficient long-range modeling with linear sequence scaling. Nevertheless, existing Mamba-based audio classification methods still lag behind mainstream Transformer-based models, suggesting that effective training strategies for fully exploiting the audio modeling potential of SSMs remain underexplored. To address this issue, we propose AD-Mamba, an architecture-complementary multi-stage knowledge distillation framework that transfers the local modeling strength of CNNs and the global contextual modeling capability of Transformers into a Mamba-based student model. Specifically, the CNN-guided stages encourage the student to adapt to local spectro-temporal structures, while the Transformer-guided stage further refines global semantic discrimination and contextual modeling. Experimental results on AudioSet show that AD-Mamba achieves 50.3% mean average precision (mAP) with only 30M parameters, outperforming representative Transformer-based and Mamba-based audio classification baselines with lower computational cost. Further evaluations under long-form audio, sparse-information, and noise-interference conditions show that AD-Mamba consistently outperforms representative CNN and Transformer baselines. When transferred to FSD50K, ESC-50, and DCASE16, the proposed model also achieves superior performance, demonstrating strong generalization across audio classification tasks.