Design and Implementation of a Real-Time Audio Spectrum Analyzer Based on ESP32 with Distributed Processing and Web Visualization

Pablo Delgado; Damian Gómez; Pablo Sumba; Alexander Chuqui; Roberto Garcia-Velez; Luis Serpa-Andrade

doi:10.1007/978-3-032-07992-3_2

Design and Implementation of a Real-Time Audio Spectrum Analyzer Based on ESP32 with Distributed Processing and Web Visualization

Pablo Delgado
, Damian Gómez
, Pablo Sumba
, Alexander Chuqui
, Roberto Garcia-Velez
, Luis Serpa-Andrade

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › peer-review

Abstract

This work presents the design and implementation of a real-time audio spectrum analyzer based on the ESP32 microcontroller. The system captures audio through I2S and processes it using digital signal techniques including DC offset removal, Hamming windowing, and Fast Fourier Transform (FFT). The ESP32’s dual-core architecture dedicates one core to intensive signal processing while the other manages WiFi connectivity and WebSocket-based web interface updates, enabling efficient parallel operation. The system includes HTTP POST capabilities for external server analysis. Experimental validation using function generators and oscilloscopes confirms the analyzer’s accuracy and stability for diagnostic, educational and experimental signal processing applications. The results demonstrate the feasibility of developing cost-effective, high-performance spectral analysis solutions, advancing telecommunications engineering toolsets.

Original language	English
Title of host publication	Proceedings of the Future Technologies Conference, FTC 2025, Volume 4
Editors	Kohei Arai
Publisher	Springer Science and Business Media Deutschland GmbH
Pages	18-34
Number of pages	17
ISBN (Print)	9783032079916
DOIs	https://doi.org/10.1007/978-3-032-07992-3_2
State	Published - 2026
Event	Future Technologies Conference, FTC 2025 - Munich, Germany Duration: 6 Nov 2025 → 7 Nov 2025

Publication series

Name	Lecture Notes in Networks and Systems
Volume	1678 LNNS
ISSN (Print)	2367-3370
ISSN (Electronic)	2367-3389

Conference

Conference	Future Technologies Conference, FTC 2025
Country/Territory	Germany
City	Munich
Period	6/11/25 → 7/11/25

Bibliographical note

Publisher Copyright:
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2026.

Keywords

Audio spectrum analysis
Digital signal processing
Embedded system
ESP32
FFT
Hamming window
HTTP POST
I2S
WebSocket
WiFi

Access to Document

10.1007/978-3-032-07992-3_2

Cite this

Delgado, P., Gómez, D., Sumba, P., Chuqui, A., Garcia-Velez, R., & Serpa-Andrade, L. (2026). Design and Implementation of a Real-Time Audio Spectrum Analyzer Based on ESP32 with Distributed Processing and Web Visualization. In K. Arai (Ed.), Proceedings of the Future Technologies Conference, FTC 2025, Volume 4 (pp. 18-34). (Lecture Notes in Networks and Systems; Vol. 1678 LNNS). Springer Science and Business Media Deutschland GmbH. https://doi.org/10.1007/978-3-032-07992-3_2

Delgado, Pablo ; Gómez, Damian ; Sumba, Pablo et al. / Design and Implementation of a Real-Time Audio Spectrum Analyzer Based on ESP32 with Distributed Processing and Web Visualization. Proceedings of the Future Technologies Conference, FTC 2025, Volume 4. editor / Kohei Arai. Springer Science and Business Media Deutschland GmbH, 2026. pp. 18-34 (Lecture Notes in Networks and Systems).

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title = "Design and Implementation of a Real-Time Audio Spectrum Analyzer Based on ESP32 with Distributed Processing and Web Visualization",

abstract = "This work presents the design and implementation of a real-time audio spectrum analyzer based on the ESP32 microcontroller. The system captures audio through I2S and processes it using digital signal techniques including DC offset removal, Hamming windowing, and Fast Fourier Transform (FFT). The ESP32{\textquoteright}s dual-core architecture dedicates one core to intensive signal processing while the other manages WiFi connectivity and WebSocket-based web interface updates, enabling efficient parallel operation. The system includes HTTP POST capabilities for external server analysis. Experimental validation using function generators and oscilloscopes confirms the analyzer{\textquoteright}s accuracy and stability for diagnostic, educational and experimental signal processing applications. The results demonstrate the feasibility of developing cost-effective, high-performance spectral analysis solutions, advancing telecommunications engineering toolsets.",

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doi = "10.1007/978-3-032-07992-3\_2",

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Delgado, P, Gómez, D, Sumba, P, Chuqui, A, Garcia-Velez, R & Serpa-Andrade, L 2026, Design and Implementation of a Real-Time Audio Spectrum Analyzer Based on ESP32 with Distributed Processing and Web Visualization. in K Arai (ed.), Proceedings of the Future Technologies Conference, FTC 2025, Volume 4. Lecture Notes in Networks and Systems, vol. 1678 LNNS, Springer Science and Business Media Deutschland GmbH, pp. 18-34, Future Technologies Conference, FTC 2025, Munich, Germany, 6/11/25. https://doi.org/10.1007/978-3-032-07992-3_2

Design and Implementation of a Real-Time Audio Spectrum Analyzer Based on ESP32 with Distributed Processing and Web Visualization. / Delgado, Pablo; Gómez, Damian; Sumba, Pablo et al.
Proceedings of the Future Technologies Conference, FTC 2025, Volume 4. ed. / Kohei Arai. Springer Science and Business Media Deutschland GmbH, 2026. p. 18-34 (Lecture Notes in Networks and Systems; Vol. 1678 LNNS).

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › peer-review

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AB - This work presents the design and implementation of a real-time audio spectrum analyzer based on the ESP32 microcontroller. The system captures audio through I2S and processes it using digital signal techniques including DC offset removal, Hamming windowing, and Fast Fourier Transform (FFT). The ESP32’s dual-core architecture dedicates one core to intensive signal processing while the other manages WiFi connectivity and WebSocket-based web interface updates, enabling efficient parallel operation. The system includes HTTP POST capabilities for external server analysis. Experimental validation using function generators and oscilloscopes confirms the analyzer’s accuracy and stability for diagnostic, educational and experimental signal processing applications. The results demonstrate the feasibility of developing cost-effective, high-performance spectral analysis solutions, advancing telecommunications engineering toolsets.

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Delgado P, Gómez D, Sumba P, Chuqui A, Garcia-Velez R , Serpa-Andrade L. Design and Implementation of a Real-Time Audio Spectrum Analyzer Based on ESP32 with Distributed Processing and Web Visualization. In Arai K, editor, Proceedings of the Future Technologies Conference, FTC 2025, Volume 4. Springer Science and Business Media Deutschland GmbH. 2026. p. 18-34. (Lecture Notes in Networks and Systems). doi: 10.1007/978-3-032-07992-3_2