Production company Spiritland Productions deployed a Solid State Logic System T TCA Flypack on a landmark project to record a live performance by Max Richter of his Hamnet soundtrack at Southwark Cathedral to be cut to vinyl at Abbey Road Studios in real time. The challenges were the lack of nearby parking and power provision for an OB truck at the cathedral prompting an approach that combined local mixing and remote control.
Rather than moving audio off-site, Spiritland brought the processing on-site and moved only the control data. Two redundant SSL T25 Tempest Engines were deployed at Southwark Cathedral, handling the full mix locally at ultra-low latency. A PC running TCA software provided comprehensive control of the Flypack system.
Six miles away at Abbey Road Studios, engineer Rupert Coulson operated the mix remotely from an SSL S500 control surface, with every adjustment transmitted across the public internet while the audio processing remained at the cathedral.
‘As far as Rupert was concerned, he was using the SSL surface in the truck as if we were parked outside,’ says Spiritland Director, Antony Shaw.
‘There was no obvious latency. There was probably between 30ms and 40ms of delay between moving a fader and hearing a difference on the return feed, which for that kind of slow-moving, swelling music was neither here nor there.’
The Flypack handled a line list that ran to around 120 inputs at 96kHz. Total control data bandwidth across the link was approximately 40Mbps, made up of the control stream plus a small number of audio feeds. Usefully, choosing on-site mixing means that the data rate is a constant; it is much lower than it would be if all audio channels were being moved across the link and does not increase with the number of inputs being mixed.
The network infrastructure meant that neither end of the pipeline required a public IP address, and all traffic was routed through a single cloud endpoint. Redundancy was provided by the cathedral’s house internet connection, two bonded Starlink terminals outside, and two 4G boosters, making a total of five IP connections. Priority was given to the stereo master feed being cut to vinyl rather than console control, on the basis that the SSL engines would continue processing in their last known state if control was temporarily lost.
Other data carried over the link included four two-way communication channels, video for PTZ cameras at both locations to provide each team with visibility of what was going on at either site, and a GPIO trigger from the Abbey Road comms panel that drove a QLab display in the cathedral showing Vinyl Cutting or Standing By messages.
From the truck, a Dante connected stagebox fed the stereo master into Abbey Road’s cutting chain. Multitrack machines at Abbey Road were also under remote control from the truck, allowing virtual soundcheck to proceed as normal.
‘Rupert walked away saying that it sounded as good as the album,’ Shaw says. ‘He’s a big SSL fan, as are we. The summing buses sound so good – we don’t know why, but they stand worlds apart from other manufacturers. We love the ability to do high channel counts, and being able to do the console configuration and the path split up as you want with very little restriction. And then of course there’s this remote working aspect, which is slightly different from how everybody else is doing it, and really works for live music.’
A major benefit of the Spiritland deployment is that the architecture is not venue-specific. This is a quickly deployable and easily repeatable workflow which doesn’t require dark fibre or leased lines. With larger SSL Tempest engines, Spiritland says the same approach can support up to 800 paths over the same 40Mbps public internet connection. The company sees direct application to festival sites, where 100Mbps symmetric connectivity is increasingly standard, and to any large-scale live event where truck access is constrained or where a controlled remote mix environment is preferable to working on-site.
‘What we’re able to do is maintain that illusion that we could be parked outside, with everything calm and lovely at the front of the truck, while dealing with whatever the location throws at us behind the scenes,’ Antony Shaw says.
‘The Spiritland team has demonstrated exactly what SSL System T is capable of in the hands of creative engineers who really understand the platform,’ says Rob Davidson, Vice President of Console Sales at SSL.
‘Delivering a full-scale live mix of this complexity over the public internet, with no OB truck on-site and no compromise on audio quality, is a compelling proof of what this workflow can achieve in the real world.’
More: www.solidstatelogic.com