Designing a system for Online Orchestra: Computer hardware and software

Abstract

Online Orchestra sought in its pilot performance to enable musicians in four remote locations in Cornwall, United Kingdom, to make music together over the Internet. This article considers the processes by which computer hardware and software platforms were selected, integrated and optimized for the performance. Starting with an overview of guiding design principles, details of the computer hardware and software platforms used are provided. Audio-and video-streaming solutions are surveyed, leading to a detailed analysis of JackTrip and its deployment in the final system. The network environment in which the Online Orchestra performance took place is also considered, including specifications of each of the four venues.

Telematic performance and the challenge of latency

“…After the results of the latency measurement tests were evaluated, it was determined that audio latency change over time had to be considered in the design of the audio system for Online Orchestra. Because of the star topology of the audio-streaming system (see Prior et al 2017a), the total audio latency between two nodes would be the addition of the latency of two peer-to-peer connections: Ôtotal node-to-node latency (node 1 to node 2) = latency of peer-to-peer connection 1 (node 1 to server) + latency of peer-to-peer connection 2 (server to node 2)Õ. It was estimated that the latency between two nodes would be at least twice as much as the latency measurements from the above tests (tests were conducted in a very good connection so it was anticipated that there would be more latency in the other locations).…”

“…After careful consideration, it was decided that the best-performing video-streaming solution for Online Orchestra was a video chat service for Telemedicine called VSee (see Prior et al 2017a; see also Chen 2008). VSee provided the most suitable features for the video-streaming system as required by Online Orchestra, including multiwindow peer-topeer teleconferencing and flexible user settings.…”

Designing a system for Online Orchestra: Peripheral equipment

“…As such, a starting assumption was that the higher the quality of audio and visual streams, the greater the sense of connection and immersion would be. However, as described in Prior et al 2017, an important feature of Online Orchestra was that it would operate across standard, domestic broadband connections. With this in mind, data bandwidth was of primary concern from the outset of the project: higher quality streams consist of larger amounts of data.…”

“…Given the primacy of audio in musical performance, greater focus was placed throughout the Online Orchestra project to optimizing the audio quality over the video quality: notionally, it is less significant that musicians can see one another at high resolution than it is that they can hear each other at high resolution. Moreover, the data size required to stream high-definition video would be a significant challenge in the context of available bandwidths at the remote locations used for the pilot performance (see Prior et al 2017).…”

Designing a system for Online Orchestra: Microphone evaluation and cost-benefit analysis

“…The project resulted in a pilot performance involving four locations around Cornwall, United Kingdom. In the two preceding articles in this special issue of the Journal of Music, Technology and Education (see Prior et al 2017aPrior et al , 2017b, the computing and peripheral equipment deployed in the pilot performance is described, along with a rationale for these choices. The final design required many components -microphones, mixers, audio interfaces, speakers, cameras, screens, computers, routers, converters, wires/connectors and software -giving rise to many potential configurations.…”