Produced by outdoor arts experts Walk the Plank, The Return of Colmcille packed in an array of performances and parades in the 30 hours preceding the unforgettable Showdown on the Foyle.
The climax concluded an epic two week journey of a traditional Irish rowing boat from the Isle of Iona, symbolically enacting the Irish saint's return back to the city he founded. Legend has it that, while in Scotland, the saint banished a 'ferocious water beast' to the depths of Loch Ness. Having followed Colmcille back to the city, the 8 June saw Nessie swim up the River Foyle and seek her revenge.
The showdown started with the monster - a converted sand barge jammed with production and pyrotechnic technology - over a mile downstream of the city's Peace Bridge. From here, roaring and breathing fire, it moved up towards the bridge to be confronted by Colmcille - and, of course, defeated by the saint and the will of thousands of spectators lining the bank.
"The audio had to achieve three things, all at the same time," says Melvyn Coote, managing director of the event's audio production company tube UK. "Firstly, we had to ensure that an audience 750m wide and up to 15m deep was always looking in the right direction at the right time - at the monster, at Colmcille or at the choir on the Peace Bridge.
"Secondly, we had to ensure that the sound from every element of the production - which included live narration, playback of suitably dramatic music on playback and the live choir - was also correctly delayed to multiple PA stacks along the river bank, so all parts of the audience heard it clearly and in sync with what they could see.
"Thirdly, we had to ensure that the monster's sound effects, coming from a PA on the dredger itself, reached different parts of the huge audience area simultaneously and tightly synchronised with the rest of the production - while all the time it was moving up river."
Needing complex delay matrices to achieve these aims, Melvyn and front of house engineer / system programmer John Redfern chose Yamaha DME digital mixing engines as the solution.
"We are experienced in delivering this kind of giant 3D soundscape with Walk the Plank projects. However, the real difficulty was the fact that the focal object - the monster - was moving significant distances. So we had to track that movement and constantly adjust the delays in the system as it moved," he says.
The live and recorded audio was mixed on a Yamaha CL5 console and two Rio3224-D i/o units in a cabin on the riverside. Alongside them were a pair of cascaded DME64N digital mixing engines with Dante interface cards, programmed with multiple delay matrices to ensure that the sound was clear across the whole, vast area.
Adding a further layer of complexity was the monster's sound effects, which were sent wirelessly from the CL5 to the dredger. An onboard Yamaha LS9-16 console and DME24N submixed the sounds, before broadcasting them through the onboard loudspeakers. At the furthest point, this meant sending the sounds from the cabin to the dredger nearly a kilometre of delay time 'early', so they would be broadcast from the dredger at the right time.
As the 'monster' made its way up the river, the onboard crew had 16 pre-programmed GPS waypoints, corresponding with different length delays, where the DME24N was adjusted to bring it into sync with the shore audio system.
"We needed a huge amount of continually-chan
