Ranked among the most treasured examples of British heritage, St George’s Chapel at Windsor was built in the 15th century by King Edward IV, and has been the setting for many royal services and weddings. It remains a chosen burial place for the British royal family – most recently Queen Elizabeth the Queen Mother and Prince Philip, Duke of Edinburgh – to the present day.
Recently, Whitwam AV Integration installed a modern and sympathetically styled audiovisual system that has transformed the way that words and music are experienced throughout the building, blending imperceptibly with the historical setting.
The loudspeaker system from K-array focuses on providing vocal intelligibility in an acoustic environment with a typical RT60 of three or four seconds, so the audio design emphasised the placement of sources relatively close to the listener to increase direct sound and reduce reflections. Vyper line arrays form the nucleus of the widely distributed loudspeaker system for the nave, with low frequency reinforcement from Rumble-KU44 subwoofers hidden behind grilles in the floor where old heating pipes had once been.
Each of the pillars lining the nave carries Vyper-KV52 line arrays; single enclosures on the outsides facing into the side aisles, and double-stacked enclosures directed toward the seating areas to give additional throw towards the middle of the building. Increasing the speaker count not only reduces the average audio path to the congregation, but also fills gaps between the pillars and heightens intelligibility.
Floor-mounted Kobra-KK52 line arrays are placed for additional sound reinforcement in the Bray and Rutland chantry, and at left and right of the high altar at the east end of the quire.
All the K-array speakers were colour-matched to a RAL swatch chosen by the Surveyor of the Fabric, who picked the colour he thought best suited the stonework and the average hue of the building. They are mounted on custom brackets fabricated to fit neatly within the cleft of the pillars so that cables can run invisibly behind them, and allow the loudspeakers to be easily removed for servicing or replacement.
To accommodate the acoustic delay down the building, the K-array speakers are paired up on amplifier channels and fed with delayed audio, while channel interleaving redundancy built into the speaker assignment avoids widespread loss of audio in the event of an amplifier failure.
Loudspeaker locations in the quire were limited to the close-field. ‘For the majority of seating locations, JBL Control 52s worked well but didn’t quite fit visually in all areas, so we put in additional K-array Lyzard-KZ1s on the choir stall upstands and, thanks to their very compact dimensions, they simply disappear into the woodwork,’ Pymm says.
Between them, the Control 52 and KZ1 sub-miniature speakers (around 80 in all) provide exceptionally uniform coverage, while floor mounted K-array Rumble-KU44 subwoofers enhance the low-end response. The K-array speakers are effectively invisible, and offer highly intelligible coverage without needing energy that would otherwise unnecessarily excite the building.
The heart of the signal processing system is a Dante enabled QSC Q-Sys Core510i control processor with analogue audio input and output cards, providing microphone switching and volume level adjustment all managed by a Crestron system. The building is split into 24 zones arranged in several bays down the nave plus three in the quire, as well as the high altar and the side aisles – all individually controlled. Audio distribution from processors to the Yamaha amplifiers driving the speaker systems is accomplished via Dante while there is also Cat5 infrastructure installed around the building.
‘Crestron touchscreens provide the intuitive user interface that enables the staff – who are non-technical – to switch on the audio system with one touch and assign sources to various zones using a graphical representation of the building,’ Pymm says. ‘They can adjust volume levels, adjust the mix among a number of live microphones and also control some of the video routing via the touchscreens distributed throughout the building.’
Three central equipment racks located in the south quire aisle house hardware that allows operation and monitoring of the whole audio/video system from a central point, including the Yamaha power amplifiers, Crestron touchscreen and Marshall video monitors, Fostex RM3 monitor speaker and Tascam SS-CDR250N multi-format audio recorder that allows music tracks to be cued up and played remotely.
The organ loft has its own dedicated sound and vision facility, with a Crestron touchscreen, JVC zero latency video monitor and pair of KEF monitors, allowing the organist to see and hear everything and with the ability to adjust audio levels if needed. A pair of Panasonic AW-UE70 4K PTZ high-definition cameras with preset view positions are installed in the organ loft, one facing west towards the nave and the other covering the quire, which enable the organist to watch for processions entering the North door, and to see the conductor’s cues.
‘In the past, the organist had to do this by line-of-sight with mirrors, but today the very low latency of the cameras ensures that he can easily synchronise with the conductor’s down beat at all times,’ Pymm says. ‘He has pair of KEF speakers and headphones to give him a direct way of hearing the choir rather than acoustically with the inevitable building delay. And there is a miniature Shure SM11 microphone placed halfway down the quire so that he can hear the conductor’s instructions to the choristers and lay clerks.’
Microphones from Audio Technica, mostly ES935ML6 microline capsules on custom mounts with a push-to-talk switch and status LED, are positioned in around the building and within the woodwork and fabric of the quire. Sennheiser 2000 series radio mics allow hand-held or stand mounted use anywhere in the building, while for music Sennheiser MKH8040 condenser microphones are partially hidden behind the loudspeakers in the nave for the choir so that the organist can hear them clearly.
These mics also feed the induction loops in the nave and quire so that the hard of hearing can hear the speech and choir as well as the ambience of the building. Microphones can be plugged in to floor boxes and connection panels in locations around the building, using seven-pin XLR connections to provide audio and switching, and these all tally up with the inputs on the Q-Sys DSP.
‘The key to success at St George’s Chapel has been the way that the equipment all fits together to overcome the acoustic and visual challenges they had in the past, and the simplicity with which it can be operated given the vast range of different events that routinely happen in the chapel,’ Pymm concludes. ‘The staff don’t have to worry, or even think about, the technology, it all just works quietly and neatly in the background.’
More: www.whitwamavi.co.uk
