Sky UK has recently moved the whole of its Sky News operation into new, state-of-the-art facilities in the Sky Studios building on the Sky TV campus in Osterley, West London. Described as being both the most sustainable broadcast facility of its kind in Europe as well as the most technologically advanced, the Sky Studios project is set to completely change the way that Sky TV works and the scope of content they deliver.
Sky Studios is now home to a brand-new, purpose-built digital news production facility comprising two production galleries, three studios and the newsroom as well as all associated staff, functions and facilities. The new complex is designed to consolidate the various strands of journalism and production workflows to allow better collaboration and more efficient use of content across different output platforms. According to Tom Pidsley, Project Lead for Sky Production Services who oversaw the audio aspects of the technical installation, it was the ideal opportunity to move part of their workflow over to IP. “This was our first toe in the water with Audio-over-IP, so we have a way to go before we are fully AoIP, but we’re already appreciating the difference,” he commented. “We elected to use RAVENNA as our main audio transport technology to ensure maximum compatibility with future video standards such as SMPTE ST-2110, as well as current compatibility with AES67. It suits our purpose perfectly.”
Currently, the main areas that have been moved over to an IP workflow are the mix/monitoring systems in the production galleries and in-ear mix/monitoring systems for the presenters. Both solutions were supplied by British broadcast audio equipment specialists, Sonifex, with the IEM mixer systems being specially designed for Sky TV to their bespoke specifications.
Sky has deployed around 20 of Sonifex’s award-winning AVN-PXH12 RAVENNA-enabled mix/monitor units across all the production galleries. The AVN-PHX12 is a 1U 24 x AES67 stream input mixer monitor that enables more flexible source monitoring than traditional analogue units. Pidsley described how the selection of the Sonifex units came about:
“In all of our production galleries, old and new, each operational position is equipped with a PC, a Talkback panel, a video monitor with source selector panel, and an audio monitor panel, plus any specific hardware required for the particular role,” he said. “For this project, we had an opportunity to revise how we managed the audio monitoring – previously we had used analogue mixers fed with multiple audio sources, requiring lots of patchbays, audio distribution amps, and a lot of copper wiring. Our application seemed ideal for trying out AoIP with its inherent distribution capability, so we went out to tender with a general specification based on IP resulting in a contract with Sonifex for their AVN-PXH12 unit.”
“In our installation, this is fed with local PC output, Talkback panel outputs (for mixing into headphones when used), audio streams from the selected video source, Programme Sound, Production Talkback, Presenter pre-fade listens, and other individual sources as required. The majority of the inputs arrive via a RAVENNA AoIP network implemented to link our Calrec audio console and the Sonifex products. In use, the operator can quickly adjust the mix between sources, as well as either mute or “Solo” any source as required. Audio activity on any source is indicated by different colour illumination of the volume controls, making it simple and intuitive to determine the source of each audio stream. It is also possible to direct the audio from each source to Left, Right, or Both (in stereo) sides of headphones when used, enabling separation of signals.”
Pidsley and his team are very pleased with the results, not least because of the vastly reduced installation costs, both in terms of time and materials – the savings in copper wiring alone are huge, and of course no need for the ranks of patchbays previously required: “The ability to change any audio source feeding any of the mix monitor unit inputs via a web browser is invaluable,” remarked Pidsley. “Previously we would have had to physically re-patch via the patchbay, or worse still, re-wire. With the new Sonifex AoIP units, production staff know that they can ask the Sound Supervisor to switch sources and it will be actioned immediately. Furthermore, this system enables us to have twice as many sources available as our previous analogue units, making it bigger, faster, more flexible and easier to implement.”
Regarding the Presenter in-ear monitoring systems, the challenges were rather different. Sky News presenters are used to having full control of each individual source that they hear in their IEMs while on air. Previously this had been achieved with a small local mixer that was fed with four sources: PTB (open talkback from the gallery director); switched talkback (producer key to presenter); programme sound source (playback or live external feed); and custom source (non-programme sound source monitored for up-to-the-minute info, e.g. sports commentary, news conference, translation etc.) Later solutions provided serial control of centralised mixers but still required audio control to be routed separately.
Sky approached Sonifex for a design that provided multiple centralised mixers controllable by presenters and/or technicians in parallel, with routing in and out of the mixers on AoIP, and audio delivered to a headphone jack on the controller unit. Additionally, because control of studio floors is frequently switched between galleries, Sky needed the ability to switch groups of remote controllers (presenter units) between different mix engines. The remotes needed to be small and ideally powered on the same connector as the data and audio.
Sonifex developed the AVN-MPPR 4-channel AES67 presenter in-ear monitoring remote controller. An 8 x 4 channel mix engine at its core enables up to 32 remote presenter units to alter the mix output levels of one of eight Virtual Mixers (VMs), each one of which offers four mono channels. Multiple units can simultaneously control any of the eight VMs in the main mix engine with the VM number displayed on the front panel. A technician version of the remote located in the Sound Control Room is able to oversee all eight VMs and adjust levels for presenters if required. Audio is transported from the main mix engine to the remote units via RAVENNA/AES67 with a single PoE (Power over Ethernet) Neutrik Ethercon network connection.
“AoIP using PoE network capability fitted the bill perfectly,” said Pidsley. “Sonifex were able to meet our design challenges and even offer additional functions and improvements like GPI switching/indicating as well as a dedicated technician version of the presenter remote with built-in management facilities in a hardware GUI. Throughout the tender and subsequent contract process, Sonifex showed an ability to understand and improve on our requirements and to build and document accordingly, making it easy for our implementation engineers to integrate the products with the rest of the project.”
“The system works really well, allowing the presenters to manage their audio sources as required and concentrate on doing what they do best! Our Sound Supervisors are able to see at a glance how the presenters’ units are set and if necessary make adjustments on their behalf with automatic monitoring of the corresponding audio. It’s an excellent solution.”
“Overall, we’re very pleased with the results of our collaboration with Sonifex who have been helpful and supportive throughout, and of course the performance of the RAVENNA-based AoIP system has significantly improved our workflow,” continued Pidsley. “My role as Project Lead is to ensure that Sky’s technical projects deliver real benefits for the production and operational teams that take over once the project is delivered. I think we can safely say that mission has been accomplished, and we will definitely consider integrating more IP workflows throughout our facilities in the future.”