Inside Out

Austria’s Bregenz Festival has a new sound system designed to replicate the acoustics of a concert hall in a stunning open-air-setting

The Bregenz Festival is world-famous for its unique setting with 7,000 spectators seated on the shore of Lake Constance, facing a floating stage which is the (world’s) largest of its kind. This special venue has defined the Festival since it was founded in 1946; it has been extended and enhanced over the long years, ultimately becoming one of Europe’s premier cultural events. With the Wiener Symphoniker as the resident orchestra since decades and an extraordinary singer cast, the Festival is also characterized by its artistic top level.

Striving for the perfect sound has always been one of the central aims of the Festival. With amazing effort and persistence, over the years and step by step, the audio team of the Festival has developed the unique sound Bregenz is famous for. A perfect localisation of the singers on the 50 m wide stage embedded in a spectacular broad and transparent orchestra sound is one of the keys to the Festival’s outstanding success.

Every two years, there is a new opera production which – in typically sold out performances – attracts nearly 200,000 visitors annually.

Sensational, extraordinary and refreshing, the production of Rigoletto in 2019/2020 has also been acclaimed for its technical brilliance. The highly motorized stage set with a gigantic moving clown head and his flexible hand is in a league of its own. Backed by a technical effort which goes far beyond the possibilities of a regular opera house, the director and stage designer Philipp Stölzl has created incredible images and impressions against the backdrop of the nocturnal lake.

This production was also the first to use the newly developed sound system BOA 2.0, which stands for Bregenz Open Acoustics. The main goal of the new setup has been to acoustically move all the seats of the open-air venue into a concert hall. Actually, into a concert hall providing the stirring and enthralling sound that matches the impressive visual appearance of the venue. And indeed, the new immersive sound experience mesmerizes the audience, delivering both the sheer power and intimate delicacy of Verdi’s dramatic score.

The new system utilizes 29 masts surrounding the audience area, each equipped with carefully aligned loudspeakers on two or three height levels, respectively. The large extent of the seating area presents a big challenge for the setup concerning the delay between the direct sound from stage and the enveloping sound energy. Comprehensive simulations and comparison tests on site showed that the K&F SPECTRA 212 convertible array speakers were the perfect tool in this demanding situation. With their precise coverage and fitting size, it is possible to outwit physics and literally shape the walls of the virtual concert hall as needed. Near-field coverage is supplied by a K&F CA 1001 CX, a coaxial speaker that was designed specifically for this installation. With the uniform and broad directivity of this speaker type, the edges of the audience area can be covered by a relatively small number of speakers.

The central element of the new installation is the VIVACE electronic acoustics processor by MÜLLER-BBM. Known from classical acoustic enhancement applications in famous venues worldwide, the creative flexibility of the system is used in Bregenz to precisely design a concert hall sound for the audience. The system processes the wireless microphones from the singers on stage as well as the input of the orchestra playing live in the concert hall of the Festival. Based on impulse responses of exemplary concert halls and opera houses, the input is converted into reflections and reverberation which are transmitted via 82 individually controlled loudspeakers.

Acclaimed by critics, the new setup proved to be the next big step in the journey of the Bregenz Festival which reliably delivers extraordinary, memorable and lasting impressions. Frequently, sound is not consciously perceived as a major contribution to this experience. Bregenz is different: Its overwhelming acoustics is always a vital part of the wonderful memories created here.

„Bregenz Festival didn’t shy away from the cost – a hefty 2.5 million euros –for completely renewing the innovative 15years old Bregenz Open Acoustics system and taking it to the next level. The existing speaker ribbon was replaced by 29 speaker masts. What worked excellently before sounds phenomenal now.“ Charles E. Ritterband, klassik-begeistert.de

This article was first published in Auditoria 2020 Volume Two
https://auditoria.mydigitalpublication.com/publication/?m=63042&i=663365&p=28&ver=html5