CHORAS: Building a Community Hub for Open-Source Room Acoustics Simulation
by Maarten Hornikx, Silvin Willemsen Eindhoven University of Technology
In the evolving landscape of room acoustics, open-source software is gaining traction. Such shared software supports collaboration and thereby has the potential to accelerate science, and it improves reproducibility and thereby the quality of science. Moreover, it may increase the impact of research by increased usage of the software and accelerated industrial uptake.
Some examples of open-source room acoustics software are Pyroomacoustics [1], RIR-Generator [2], gpuRIR [3], and SoundSpaces [4]. An overview of the state of open source room acoustics software as of 2024 can be found in Hornikx et al. [5]. The existing open source room acoustics tools may be difficult to access, install or use, and often exists as raw code repositories rather than user-friendly applications. They lack standardization in input/output formats, and are not widely adopted—limiting the opportunity for shared user experience and feedback.
Also, the tools may have different standardization in input/output formats. Finally, some of the tools, despite their potential value, have not been used such that experience of users cannot be shared.
To take the next step in the open-source room acoustics arena, a research project was funded by the Dutch Research Council (NWO). This project focuses on two key goals:
- Advancing and validating two complementary room acoustics modeling methods for practical use.
- Building a sustainable software community where researchers and practitioners can collaborate, share, and contribute to open-source simulation tools.
The involvement of end users is crucial in this project. They will help to benchmark the developed modelling methods and test the prototype software of the community platform.
At the heart of this project is CHORAS—the Community Hub for Open-source Room Acoustics Software. Developed at Eindhoven University of Technology, CHORAS is a web-based platform that allows users to run room acoustics simulations through an intuitive, platform-independent interface. It serves as a modular front-end for simulation methods, enabling researchers to plug in their own open-source back-end software.
Currently, CHORAS supports two simulation methods developed within the NWO project: the Diffusion Equation (DE) method and the Discontinuous Galerkin (DG) method. The next step is to collaborate with developers of other open source room acoustics software to connect their software to CHORAS too. In that way, the open source room acoustics software becomes more accessible and comparable, with different software accessible via one web-based user interface. This will allow users to explore and compare both emerging and established simulation techniques. Moreover, it may help to develop the collaborative community around the software that can help it to grow further.
In CHORAS, users can upload 3D models, configure sources, receivers, and materials, and run simulations directly from the browser. Results include key acoustic parameters (e.g., T30, C80, D50), energy decay plots, and auralizations—allowing users to listen to the simulated space.
The platform is open-source and available on GitHub [6], with documentation on running the software. The technical features of the CHORAS interface can be found in the conference paper about this platform [7], presented at Forum Acusticum in Malaga, June 2025.
Looking ahead, apart from the integration of more simulation methods, the following developments are planned for CHORAS: full deployment of CHORAS to the cloud, support for parallel simulations, enhanced user interface and plotting features.
As for other open source software initiatives, collaborative events will help to bring the community further. The next major event is a hackathon that will be organized during the 4rd Autumn School Series in Acoustics (ASSA) held in Eindhoven in November 2025.
CHORAS is a call to action for the room acoustics community. By contributing to the platform or by actively using it, you help build a more open, efficient, and collaborative future for room acoustics simulation.
[1] https://github.com/LCAV/pyroomacoustics
[2] https://github.com/ehabets/RIR-Generator
[3] https://github.com/DavidDiazGuerra/gpuRIR
[4] https://github.com/facebookresearch/soundspaces-challenge
[5] Hornikx, M., Wang, H., Fichera, I., Paganini, L., Nolte, A. and Serebrenik, A., 2024. Exploring the current landscape of open research software in room acoustics. In INTER-NOISE and NOISE-CON Congress and Conference Proceedings (Vol. 270, No. 6, pp. 5875-5884). Institute of Noise Control Engineering.
[6] https://github.com/Building-acoustics-TU-Eindhoven/CHORAS
[7] Willemsen, S., Teymoori, H., Fichera, I., Wang, H., Nolte, A., Serebrenik, A., Hornikx, M, 2024. Towards a community hub for open-source room acoustics software. In Proc., Forum Acusticum, Málaga, Spain.