Confirmation to completion in only 4 weeks
Following a comprehensive evaluation of the existing audio system in Al Bayt Stadium, the Supreme Committee elected to proceed with our overlay loudspeaker system design. The timeframe was extremely tight and the system design was modified from an ideal layout to one that utilised the existing rigging points. This strategy avoided additional engineering and top-rigging works that would have slowed the process down significantly.
The overlay design consisted of five elements:
Upper bowl coverage - discussed below.
Lower bowl coverage - discussed below.
Sub-bass extension - discussed below.
Fill systems for shadowed areas - this consisted of a pair of L-Acoustics X12 loudspeakers mounted to the rear of the two scoreboards to provide coverage of the shadowed seats.
Special array specifically for coverage of the player lineup location for the National Anthems (this array of 3 Kara II elements can be seen in the photo above).
UPPER BOWL COVERAGE
Distributed arrangement of 16 arrays of L-Acoustics K2
All 16 upper bowl arrays consisted of 9 elements of L-Acoustics K2 as shown in the photo totalling 144 K2 powered by 48 LA12X amplified controllers.
The East and West arrays had the amplifiers flown with the loudspeakers to reduce cable length. The North and South arrays had the amplifiers on the catwalk above.
Specific parts of the upper bowl system were attenuated as required by FIFA to enable the live commentary from the media tribune.
LOWER BOWL COVERAGE AND SUBS
Distributed arrangement of 16 arrays of L-Acoustics Kara II and six sub-bass arrays
12 of the 16 lower bowl arrays consisted of 9 elements of L-Acoustics Kara II as shown in the photo, with the corner arrays consisting of six elements. The total Kara II quantity was 132 elements powered by 32 LA12X amplified controllers.
Six arrays of three L-Acoustics KS28 were distributed around the venue, each in a cardioid configuration with the top element reversed.
AVB and Optocore
Primary signal delivery to the amplifiers was via an AVB network using L-Acoustics P1 talkers and Luminex Gigacore 26i network switches.
Secondary signal delivery to the amplifiers was via a closed-loop Optocore network with X6R-FX providing AES/EBU digial audio with the amplifiers in fall-back.
The system was configured in an alternating left / right stereo arrangement.
SYSTEM CONTROL AND MONITORING
L-Acoustics LA Network Manager
The system was controlled and monitored on L-Acoustics LA Network Manager. The system was optimised within the Soundvision environment for the implementation of the automated FIR filtering.
Time alignment and final tuning was conducted onsite by our team of specialists.
The people and companies that made it happen. Thanks to Oli Crump for some of the photos.
Thanks to John McCullagh and the whole team at BWS for involving us in this project and managing the procurement and delivery of this significant piece of work. Thanks also to Jennie-lee Van Gelder, Tom Casey and the team at SC Ceremonies for initiating and guiding the project.
The Audio system was designed by Scott Willsallen with support from Ethan Curry. Our implementation team included Luis Miranda, Toby Chester, Lee Holmes, Marty Harrison, James Ghamlouch and Martin Dineley,
Thanks to Oli Crump and Robin Conway and the team from Solotech for supplying and installing the PA. Thanks to Giulio Rovelli and the team from Agora for the signal transport and project management. Thanks to Sam Carter from Unusual for the rigging and expertise.