International architectural and acoustic consultants Walter-Storyk Design Group (WSDG) worked closely with installation company Kilchenmann AG and Nexo distributor ZAP Audio on this project, which began in 2006.
One of the goals was the integration of modern technology into a faithful restoration of the building's original structure. This applied in particular to the installation of a PA system in the National Council Hall.
Giving the politicians a rare day off, the Chamber was made available for a live demo and the GEO S8's performance was measured and analysed to verify their choice. WSDG had studied various installation options using advanced acoustical computer simulation techniques to choose between four designs. "Conventional Line Array at Left-Right Position" was selected, deploying GEO S8 line array loudspeakers installed in a left-right configuration, because it offered the best SPL coverage and highest speech intelligibility for all 250 seats in the Chamber.
WSDG's project leaders Thomas Wenger and Gabriel Hauser staged a final live test for the Members of the Assembly themselves, giving them the chance to assess the new GEO S8 solution against the existing sound system. In a poll, the votes of the politicians came down clearly in favour of the newly-installed system.
After consultations with the historic building conservation authorities, installer Kilchenmann AG was able to fulfil WSDG's design concept. 7x GEO S8 cabinets were used on each side of the large wall painting that dominates the Chamber; the loudspeaker modules were fitted into purpose-built box frames with crossbars at the back, a WSDG idea executed primarily for cosmetic purposes but which also reduced the impact of fixing on the historic mural.
The National Council Hall has three distinctive zones that require sound reinforcement: the main hall, the stage area (with a distinctive presenter position and seats for the Chairpersons and clerks such as vote counters and recorders) and the balcony (for visitors and press). The GEO S8 arrays cover the main seats in the Chamber, but not the stage area - mainly due to the acoustical feedback situation and also due to the orientation of the chairpersons. A separate mini line array loudspeaker system using wideband driver units was custom-designed and built, and installed locally on top of the vintage table tops.
(Claire Beeson)
