The creation of ex-BBC sound supervisor Conrad Fletcher, Mixbus is a large-format sound recording and live broadcast vehicle built to handle audio capture at largest shows and events. Three live-to-cinema productions from the Garrick Theatre for the Kenneth Branagh Theatre Company aired to more than 41 countries recently are typical of the many high-profile events it has undertaken.

Fletcher is a longstanding user of Merging Technologies’ Pyramix DAW, and the Mixbus audio system includes Merging’s Hapi multi-format converters with Ravenna Audio-over-IP providing additional connections to the truck’s various audio workstations. The addition of a DirectOut Monotone.42 Ravenna-to-Madi bridge has significantly expanded this capability.

It soon became apparent that the mixed economy of traditional audio system clocks and network clocking provided by Ravenna’s PTP v2 required more durable management of the network clocks. Conrad looked to Aspen Media to help solve this problem, and having recently taken on the UK distribution for audio applications of the ARG Quarra range, Director Chris Collings offered Mixbus an ARG Quarra PTP Smart switch that provides a direct hardware path for PTP timing data, bypassing data queues within the switch that would inevitably delay sync packets that require the highest priority despite high network activity distributing hundreds of audio channels.

The transparent PTP provided by v2 of the PTP network timing standard also with a PTP Smart switch is the Audio-over-IP (AoIP) equivalent of the independent distribution of audio system clocks employed in all professional audio and broadcast systems.

Installing the ARG Quarra PTP Smart switch into the Mixbus’s system resulted in the Monotone display showing 100 times better jitter performance improving overall audio quality and delivering a more stable system that is better equipped to accept signals from third-party systems via Madi.