Universität der Künste Berlin
ASC brings concert hall up to the state of the art
Speech intelligibility and resonance-free reproduction in harmony with the protection of historical monuments

With 70 degree programs, the Berlin University of the Arts (UdK) is one of the world’s largest, most diverse, and most traditional art colleges and one of the few art colleges in Germany with university status. The Faculty of Music at the UdK Berlin maintains places of specialization and encounter, such as the Joseph Joachim Concert Hall. The 380-square-meter hall was modernized by Amptown System Company with a sound reinforcement system that must provide optimal speech intelligibility, the most homogeneous possible distribution of sound pressure levels across the listening areas, and minimize feedback and distracting reflections.

Comprehensive measurements of the room acoustics were carried out as a basis for planning. Ray tracing simulations were used to create an interior model for sound reinforcement planning. A precise prediction of the sound distribution in the entire hall including the reflection paths and a calculation and optimization of the achievable speech intelligibility were thus possible. As a result, it was possible to specify a main system with very high requirements for vertical bundling in order to avoid interfering reflections from the rear wall of the hall to the stage.

For this purpose, Alcons Audio QR24 loudspeakers were used, which achieve an optimal directivity for the hall while maintaining a compact design. The coverage for the front rows of seats is supported by four Alcons SR9 with which a uniform sound image is achieved. Low frequencies are realized by four Alcons BF151 mkII subwoofers. Depending on the application, these can be connected within the stage or in the area of the main systems. The mechanical handling of mobile equipment could be optimized by a number of special designs such as custom-fit transport carts and Speakon floor tanks with adaptations in 3D.
The management of room configurations and bass coupling was implemented using a powerful loudspeaker and room acoustics processor that both reduces resonances in the room and optimizes phase responses for proper acoustic summation of the main systems with the subwoofers.

Another particular challenge in the choice of sound reinforcement system was the preservation order under which the Joseph Joachim Concert Hall is located, which dictates clear ideas for the integration of the loudspeakers. With the help of a 3D animation and on-site sampling, MMT was able to convince all parties involved in the project, both acoustically and with regard to the interior architecture.
After intensive measurements, a sound reinforcement system could be handed over to the UdK, which caused enthusiasm among all participants due to an excellent speech intelligibility in combination with resonance-free reproduction down to the lowest frequencies.