Chen, RGhobakhlou, AliNarayanan, A2025-01-292025-01-292024-12-18Frontiers in Artificial Intelligence, ISSN: 2624-8212 (Print); 2624-8212 (Online), Frontiers Media SA, 7, 1499913-. doi: 10.3389/frai.2024.14999132624-82122624-8212http://hdl.handle.net/10292/18557Introduction: Musical instrument recognition is a critical component of music information retrieval (MIR), aimed at identifying and classifying instruments from audio recordings. This task poses significant challenges due to the complexity and variability of musical signals. Methods: In this study, we employed convolutional neural networks (CNNs) to analyze the contributions of various spectrogram representations—STFT, Log-Mel, MFCC, Chroma, Spectral Contrast, and Tonnetz—to the classification of ten different musical instruments. The NSynth database was used for training and evaluation. Visual heatmap analysis and statistical metrics, including Difference Mean, KL Divergence, JS Divergence, and Earth Mover’s Distance, were utilized to assess feature importance and model interpretability. Results: Our findings highlight the strengths and limitations of each spectrogram type in capturing distinctive features of different instruments. MFCC and Log-Mel spectrograms demonstrated superior performance across most instruments, while others provided insights into specific characteristics. Discussion: This analysis provides some insights into optimizing spectrogram-based approaches for musical instrument recognition, offering guidance for future model development and improving interpretability through statistical and visual analyses.© 2024 Chen, Ghobakhlou and Narayanan. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.http://creativecommons.org/licenses/by/4.0/convolutional neural networksfeature extractionfeature mapsheatmapsmusic information retrievalmusical instrument recognitionpattern recognitionspectrogram analysis46 Information and Computing Sciences4602 Artificial Intelligence4611 Machine LearningBioengineering4007 Control engineering, mechatronics and robotics4602 Artificial intelligence4611 Machine learningJournal ArticleOpenAccess10.3389/frai.2024.1499913