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This paper documents the challenges encountered during the development of a mobile web-based, real-time distributed reverberation chamber for a live concert setting. Initial efforts focused on leveraging existing open-source and commercial solutions, but these proved inadequate due to limitations in network compatibility, audio routing, and mobile device support. WebRTC emerged as the most viable option, offering peer-to-peer communication and firewall traversal capabilities. However, significant obstacles persisted, including network reliability, audio hardware/software ecosystem limitations, and debugging complexity. The project highlights the fragmented nature of real-time audio streaming technologies and the need for more transparent, reliable, and well-documented tools. Despite these challenges, the authors developed a functional web application prototype using WebRTC, Web Audio API, and custom Session Description Protocol modifications, offering insights into the complexities of deploying real-time audio systems over mobile networks. The paper concludes with reflections on speculative approaches, such as decentralized audio routing and native app development, and calls for improved documentation and standardized debugging tools to support future innovations.

Analysing spatial information within recorded music is increasingly important for audio research given the explosion of available datasets, but relevant techniques are spread over diverse fields. To address this, a systematic literature review (SLR) was conducted to ascertain all existing methods for describing the spatial features of stereophonic music. The Scopus, Web Of Science (WOS), and Semantic Scholar (SS) databases were searched on 26th February 2026, and articles were deemed eligible if the method they described included any extraction of spatial information from a music audio signal. Links and similarities were drawn between studies to identify the core methods of describing stereo image. One hundred seventy-eight articles were included, with 29 of those deemed "very relevant". The fundamental methods of extracting spatial information are detailed and a framework for creating a custom stereo image profile (SIP) is drawn up, followed by suggestions for future research. The review was limited by the substantial volume of literature to be assessed by few researchers, although this wide breadth served to mitigate bias by gathering at least one example of all existing SIP methods. Inconsistent application of terminology within the existing literature presented a significant challenge. The work was funded in part by The Knowledge Foundation (KKS).

Estimations of panning attributes are an important feature to extract from a piece of recorded music, with downstream uses suchas classification, quality assessment, and listening enhancement.While several algorithms exist in the literature, there is currently no comparison between them and no studies to suggest which one is most suitable for any particular task. This paper compares four algorithms for extracting amplitude panning features with respect to their suitability for unsupervised learning. It finds synchronicities between them and analyses their results on a small set of commercial music excerpts chosen for their distinct panning features. The ability of each algorithm to differentiate between the tracks is analysed. The results can be used in future work to either select the most appropriate panning feature algorithm or create aversion customized for a particular task.

The current practice for mixing music and speech is to decrease the volume of of the music in order to increase the intelligibility of the speech. However, it is sometime desirable to keep the music in focus, while mixing speech in another way. In VR it is common to separate sounds in space rather than changing the relative levels, but there is a lack of research on how to mix music and speech using similar techniques while retaining a pleasant listening experience. This paper describes a subjective test in which volunteering participants were asked to rate the pleasantness of music mixed with relevant speech. The speech signal was panned binaurally between 45° left and 45° right, in 15° increments, and mixed with various music tracks at equal loudness, with the hypothesis that this would improve the pleasantness ratings compared to centrally panned speech. The results indicate that the centre is not always the optimum panning position and that participants had strong individual preferences. Future work should concentrate on controlling and expanding the audio stimuli, and investigating the reasons for participants’ preferences.