Symmetry through sound: Benguela Cathedral, Angola
Situated in the southern suburbs of this prosperous West African sea port, midway between the city’s main railway station and its home team football stadium, the Cathedral of Benguela, Angola, Sé Catedral de Nossa Senhora de Fátima to give its proper name, is an imposing piece of modernist architecture. Unadorned, the massive concrete structure has a pleasing symmetry, the walls sloping inward to form a towering triangular building; as well as a focus for Christianity it is also a cool haven from the oppressive heat for its burgeoning congregation.
Like its stone built forebears in Europe, Benguela Cathedral has a booming reverberant interior, “When I first made a detailed EASE model of the cathedral the calculated reverb’ time was 5 seconds at 100 Hz,” said Burton Reid from Event Technology (ET), “the reality was no different”. Reid’s company had been charged with finding an appropriate sound reinforcement solution to a classic speech intelligibility problem. “This is an almost twenty thousand cubic metre space confined by flat concrete walls; I simulated several loudspeaker configurations before deciding upon an appropriate system.”
Based in Namibia, ET is an established Sales partner to Stage Audio Works (SAW) in South Africa; it was the range of d&b audiotechnik loudspeaker systems, which SAW distribute in the territory that offered Reid his solution. “I eventually decided upon d&b Qi7 for mains and delays, with E8s for the balcony and to provide a slight lift in the fill position at the altar. The church conducts simple services daily during the week, but at the weekend there is a small band, usually keyboard and guitars with up to six vocal inputs. For the congregation good uniform coverage was essential, but at relatively low SPLs, not something many modern systems are so good at delivering, but the Qi7 like all the d&b systems works just the same even when driven very lightly. Vocal presence and clarity is essential, the neutral balance of the d&b system unparalleled.”
The cathedral’s management committee pronounced the system perfect, “They were really pleased that the priests could now be heard by the congregation,” said Reid. “It has never sounded like this before,” added Fr Franklin from the church. “After the services we were getting ‘thumbs ups’ and smiles as the congregation left the church.”