Renkus-Heinz delivers stadium sound for home of Swiss sports

Originally built by members of FC Zürich, Stadion Letzigrund has been the home of football and ‘Weltklasse Zürich’ – one of the most renowned one-day events in athletics – since 1925. A call for the modernisation of the stadium in the late ‘90s saw the venue close its doors and reinvent itself in the summer of 2007, with an improved capacity for football, athletics and concerts.

Since then, the stadium has hosted European Championships, concerts by internationally renowned artists, and several big games for the Swiss Football League. To continue its legacy, Letzigrund upgraded its sound system with Renkus-Heinz to provide spectators with seamless audio, no matter the event.

Collaborating on the project were integrators avidec AG and audio consultants promedias AG. The events programme at the stadium changes regularly, so the system had to be weather-resistant and flexible enough to cater to speech, music and public announcements.

Consistent and balanced sound pressure levels were important, as was even coverage. Renkus-Heinz’s C Series and T Series loudspeakers in the WR weather-resistant versions delivered exactly what Letzigrund was looking for.

“Renkus-Heinz has a large range of loudspeaker systems, which meant that we were able to find the perfect solution for this project,” said Chris Steiger, CEO and founder of promedias AG. 

“We originally installed 48 CX61 models in 2022 as nearfield loudspeakers for the audience in the back rows. This year, we expanded the system further, replacing the original loudspeakers that were installed in 2007 when the stadium reopened with over 30 TX151s. This enabled us to deliver homogenous sound for all events.”

avidec installed 31 TX151s on the stadium roof to deliver powerful sound to the audience. Two loudspeakers are mounted in each front field, with one loudspeaker directed at the athletics track and the second at the front row of spectators. In the rear field, one TX151 loudspeaker provides sound for the audience at the back, and the rear three rows of seats benefit from sound provided by the additional, smaller CX61s.

“Renkus-Heinz’s T Series loudspeakers are versatile enclosures that can be integrated almost anywhere,” furthered Steiger. “The models are ideal for sports venue projects, delivering outstanding sonic performance to every area of the Letzigrund.”

The TX151s put the advancements of Renkus-Heinz into practice with their complex conic horns. These horns provide constant beamwidth and directivity without the problems of conventional rectangular horns. Featuring the same complex conic horn technology of the T Series, the CX61 models deliver high-volume output in a small enclosure, as well as low distortion and high-frequency performance power.

"avidec AG has been supporting the system since it was installed in 2007, therefore for over 17 years," Steiger continued. “The experienced technicians at avidec AG chose Renkus-Heinz’s T Series and C Series models because of their excellent dispersion angles, high SPL and weatherproof housing. 

"These models fit perfectly into the existing infrastructure. With this first conversion, we have now installed new sound in 40% of the spectator stands. We plan on integrating more TX151s next year for the middle-row and back-row seats and the field. That’s how much confidence we have in these loudspeakers.”