Following a three-year rebuild, the Workers Stadium in Beijing staged See You Summer, its first concert in the upgraded space. Home to Chinese Super League’s Beijing Guoan Football Club, the venue seats 68,000 in an international-standard football arena and welcomes live concert performances by local and international stars. The highly-anticipated See You Summer concert featured six popular musical acts from three successful seasons of the nationwide iQIYI streaming service variety show, The Big Band.

Established Chinese rock bands New Pants, Tong Young, Wutiaoren, Re-TROS, Novahearts, and Second Hand Rose performed to more than 30,000 fans in the large outdoor stadium, which features a bowl canopy design that fully covered the spectator stands. RAC Technical Director Zhou Fengxin designed a concert sound system that would provide high SPL to support the dynamic pop and rock acts while providing flexibility for the diverse range of musical instruments featured in the six bands.

Zhou worked with sought-after concert sound producer Jin Shaogang to survey the newly rebuilt venue, create a 3D representation of the space, and translate that into L‑Acoustics Soundvision to ensure an optimum sound design. During the process, they identified long reverberation times as a significant challenge. “We took note of staging and audience areas and discussed speaker deployment positions and their respective coverage areas. We saw that we needed to shorten throwing distances to achieve optimal, direct sound and reduce reflections as much as possible,” explained Zhou.

He simulated several design drafts with varying speaker heights and angles, calculating SPL with every reiteration of the system design to meet the promoter’s requirement of covering concert audience areas designated on two-thirds of the stadium’s field and the spectator stands.

A system design was chosen based on the powerful, long-throw characteristics of L‑Acoustics K1. A main left-right system of 12 x L-Acoustics K1 and 3 x Kara II speakers per side was flown above the stage, with eight K1-SB subwoofers flown behind each side. An additional six groups of 6 x KS28 subwoofers in cardioid configuration were stacked in front of the stage. The side-fill system comprised 12 x L-Acoustics K2 boxes per side, with its Panflex horizontal directivity adjusted to 70° to minimise reflections from the glass surfaces of the stadium canopy structure.

To deliver coverage to the stands surrounding the football field, twelve sets of lightweight Kara II boxes were rigged as a delay system on a flying ring truss. A second delay system comprised four stacks of three to five K2 boxes to cover the audience in the spectator stands furthest away from the stage. Here, the Panflex of the top two boxes of each stack was adjusted to 70° while the bottom three were set to 110°. Using two delay systems allowed the main system to output at lower levels, reducing reflections and effectively improving the overall consistency and coverage.

Once deployed, Zhou’s system engineering team leaned on the L-Acoustics P1 processor and M1 measurement software to achieve swift system tuning during the tight schedule between band rehearsal times. Sweep signals and the tuning process took less than a quarter-hour. However, once tuning was attained, Mr. Zhou knew the significant changes from daytime temperatures of 30°C to night-time temperatures in the teens would impact the sound during the live show. During the show, his team used the Autoclimate function of LA Network Manager to adjust to environmental changes and create consistent sound from the first musical notes of soundcheck and rehearsals to the final encore.

The result was a heart-pounding, exhilarating sonic experience for all fans. “A member of the audience praised the sound as being incredible and thanked our team for producing one of the best live concerts in recent memory. Several concertgoers were looking forward to more shows here in the Workers Stadium,” concluded Mr. Zhou.

L-Acoustics