After nearly four years in construction, Tottenham Hotspur moved into their new state-of-the-art stadium at the beginning of April 2019. SSE Audio Group was appointed to design and integrate the comprehensive audio and PAVA systems throughout the 62,000 seat stadium, including the bowl and hospitality areas, through to the dressing rooms, bars, restaurants and everything else between. The team of SSE project managers and engineers was led by Eddie Thomas, VP special projects in Europe for SSE Audio Group, and this is the audio story in his own words…
SSE Audio has a long history in tour and festival sound system rentals and, more recently, installations in venues of all kinds. My area of expertise is in the larger Special Projects, where audio plays a major role in the safety and emergency systems of the site. We have a wealth of experience working in the Public Address and Voice Alarm (PAVA) sector, designing and installing systems in, for example, The O2 Arena, Swansea’s Liberty Stadium and in safety-critical workplaces such as road tunnels and nuclear power stations.
As the official audio supplier for the stadium, Harman Professional Audio Solutions provided most of the equipment for the installation with over 5,500 JBL loudspeakers on the site, all powered by Crown Amplifiers. After the initial audio consultancy work carried out by Vanguardia, utilising a different manufacturer’s equipment, I began the task of redesigning the audio system at Spurs using the appointed Harman equipment throughout the stadium. At modern sporting facilities, our focus is on two distinct functions: providing high quality audio throughout as part of the entertainment package and delivering information, safety and evacuation announcements as part of the venue’s security and emergency procedures.
The PA systems at Tottenham can also be split into two separate elements; the main (FOH) system comprises line arrays that are flown from the stadium roof to provide audio inside the bowl; in addition, there are speakers throughout every BOH area, including concourses, private boxes, bars, toilets, car parks, etc. to ensure coverage for everyone within the complex.
All around the bowl, you’ll see the distinctive line arrays. These comprise of JBL VLA 2100 Compact cabinets with VLA C125S subwoofers. A total of 154 cabinets and 54 sub bass cabinets make up the 18 line arrays we’ve deployed. Using 3D acoustic modelling we calculated that each array should be between eight and 12 cabinets to ensure coverage to every seat. We then recommended the addition of the sub bass cabinets for each array. These are essential when you take account of Spurs’ plans to use the stadium for more than football, including the demanding audio requirements of the NFL. The sub bass cabinets are configured in cardioid configuration, which cuts down on reflections off the main stadium roof.
Each array is contained within a custom flying flame bolted directly to the stadium roof. After liaising with the stadium steelwork supplier Severfield, the frames were designed and manufactured by our in house manufacturing arm, Sigma Fabrications. Each frame was loaded with the JBL VLA 2100s and VLA C125S subs before being shipped to the site.
We also developed a special cart that allows each array to be carried and hoisted into position. The cart remains here on site for when the arrays are lowered in the future for inspection and maintenance. Jake Miller and Paul Lambert, two of SSE Audio’s most experienced project managers, have been resident on site for the past 18 months as site managers and supervisors overseeing the installation of equipment and cabling.
Throughout the concourse areas, we have installed JBL pendant and ceiling mount speakers to provide audio and deliver stadium announcements. With over 5,000 speakers required, we sub-contracted the physical BOH cable, containment and loudspeaker installation work to Tyco, before conducting testing and commissioning to bring the systems online.
The entire audio system at Tottenham’s stadium is built on a digital network. At the heart of this are a pair of QSC Q-Sys Cores. The cores provide all the digital signal processing (DSP) and signal routing for each of the 5,000 loudspeakers on site. This constitutes one of the largest Q-Sys networks we have ever assembled and we have really pushed the envelope in our exploration of its capabilities. Over the past few years, we’ve developed our knowledge and experience of the technology and it’s now our go-to solution for projects of this type.
As the system is a critical element of the fire and evacuation procedures, the network has comprehensive redundancy built in throughout. There are many levels to the redundancy: two cores run simultaneously, one as a primary system, the other as a backup. If the backup detects a failure of the primary it will changeover and take control automatically.
The main network is on a fibre optic backbone and there are two separate paths run over different physical routes to every device - in the event of a fire or other failure damaging the network in one place then there’s still a physical route in place.
Adjacent loudspeakers in any area will be on separate channels A and B, fed by different amplifiers. In the event of a failure, be it a critical one where all of one channel goes down throughout the stadium or just a single amplifier channel develops a fault, at least 50 per cent of the loudspeakers in an area will remain in operation.
In addition to the digital infrastructure, there’s also an analogue backup - ultimately, if the entire network went down we could still put out paging announcements to the entire stadium - it’s incredibly robust in terms of its fault tolerance.
AVI, the AV contractor for the project has installed hundreds of screens and local control interfaces throughout the venue, all running on a separate QSC Q-Sys network. SSE worked with AVI to bridge the audio and AV networks together, allowing audio from the screens and local interfaces to be routed to the speakers local to each screen. The system is configured so the PAVA system is always top in the priority hierarchy, so in the event of an emergency or public safety announcement, the external audio is overridden by the PAVA system.
One of our key challenges was to integrate the JBL loudspeakers with the Q-Sys platform to provide a system that not only provided flexible audio routing throughout the site but is also the robust, fault tolerant and monitored system that PAVA requirements dictate.
We worked with Harman to develop the software plugin for the Crown amplifiers, essential to provide control and monitoring for the Q-Sys system. All the Audio transport is Dante, so that wasn’t a major issue, but we developed the plugin to provide the system health over the network. For a PAVA application, not only does your system have to work, you have to be able to see in real time if a failure should occur.
Most of the programming for the project has been carried out by SSE's technical specialist Paul Todd. Paul has been instrumental in developing SSE’s knowledge and understanding of the Q-Sys system over recent years. He has developed numerous innovations using the platform across a wide range of projects that means we can deliver really complex solutions on easily understood graphical screens.
He was responsible for programming and developing the user interfaces for the system. Touch screen GUIs (graphical user interfaces) present system control in a logical and simple format. The system can be viewed on a map of the stadium, allowing the user to select a zone or zones and then route audio to their selection.
Working on a new build project of this scale obviously has its own unique challenges. There are so many different contractors and trades all working on site and you need to coordinate your work schedule with and around them. Much of this coordination was managed by our onsite project manager Jake Miller. There’d be times when we’d be wanting to install a speaker in a ceiling space, only to discover that the ceiling wasn’t built yet, so you have to reschedule your workload.
The SSE Audio team has lived and breathed this project for the past two years, so we are really pleased to see the stadium up and running and football return to White Hart Lane. Spurs can now boast an audio system to match the excellence of the whole stadium, with audio quality and high SPL delivered to every seat. It’s an incredibly flexible system, fit for the variety of applications the stadium requires and is an integral part of the public safety system.
You can also read about our experience of the stadium and Harman's involvement in the project here.
In addition, Britannia Row supplied the sound for the grand opening of the stadium, which you can find out more about here.