PAT: Parameter-Free Audio-Text Aligner to Boost Zero-Shot Audio Classification

Ashish Seth, Ramaneswaran Selvakumar, Sonal Kumar, Sreyan Ghosh, Dinesh Manocha


Abstract
Audio-Language Models (ALMs) have demonstrated remarkable performance in zero-shot audio classification. In this paper, we introduce PAT (Parameter-free Audio-Text aligner), a simple and training-free method aimed at boosting zero-shot audio classification performance of CLAP-like ALMs. To achieve this, we propose to improve the cross-modal interaction between audio and language modalities by enhancing the representations for both modalities using mutual feedback. Precisely, to enhance textual representations, we propose a prompt ensemble algorithm that automatically selects and combines the most relevant prompts from a datastore with a large pool of handcrafted prompts and weighs them according to their relevance to the audio. On the other hand, to enhance audio representations, we reweigh the frame-level audio features based on the enhanced textual information. Our proposed method does not require any additional modules or parameters and can be used with any existing CLAP-like ALM to improve zero-shot audio classification performance. We experiment across 18 diverse benchmark datasets and 6 ALMs and show that the PAT outperforms vanilla zero-shot evaluation with significant margins of 0.42%-27.0%. Additionally, we demonstrate that PAT maintains robust performance even when input audio is degraded by varying levels of noise. We make our code publicly available.
Anthology ID:
2025.naacl-long.616
Volume:
Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers)
Month:
April
Year:
2025
Address:
Albuquerque, New Mexico
Editors:
Luis Chiruzzo, Alan Ritter, Lu Wang
Venue:
NAACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
12376–12394
Language:
URL:
https://preview.aclanthology.org/landing_page/2025.naacl-long.616/
DOI:
Bibkey:
Cite (ACL):
Ashish Seth, Ramaneswaran Selvakumar, Sonal Kumar, Sreyan Ghosh, and Dinesh Manocha. 2025. PAT: Parameter-Free Audio-Text Aligner to Boost Zero-Shot Audio Classification. In Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers), pages 12376–12394, Albuquerque, New Mexico. Association for Computational Linguistics.
Cite (Informal):
PAT: Parameter-Free Audio-Text Aligner to Boost Zero-Shot Audio Classification (Seth et al., NAACL 2025)
Copy Citation:
PDF:
https://preview.aclanthology.org/landing_page/2025.naacl-long.616.pdf