Wide Area Audio Synchronisation

In this short paper we describe a Wide Area Audio Synchronisation demonstration using the Quality of Service (QoS) facilities of the Nemesis operating system. The Nemesis operating system is a result of the ESPRIT funded Pegasus I research project.

A stereo audio stream is split with each channel being input to one of two distinct network digitisation devices; one of the resulting streams is sent via a wide area network to a foreign country, and the two streams are then resynchronised entirely in software. Playout on a digital speaker device was analysed and found to be correct to within 150 us, which is the resolution of the timer hardware on the workstation used. The accuracy of this resynchronisation demonstrates the effectiveness of the Nemesis QoS techniques