Koekelberg basilica, Brussels Belgium
In houses of worship, intelligibility of the spoken word is crucial, something both the clergy as well as the technical crew of God’s houses have become aware of. The Belgian national basilica, the “Basiliek van Koekelberg”, is the country’s largest church, (the world’s fifth largest basilica) and used for big national ceremonies and services with international acclaim.
It’s cross shaped base-form with a 2500 capacity main nave and big side aisles, each with a capacity of some 250 visitors, a depth of 60m./197ft. plus the 7 seconds reverb made the assignment to provide accurate sound reinforcement a true challenge for audio company Pa-P.A and Alcons’ engineer Philip de Haan.
“The intelligibility over the entire space is remarkable…the vocals crystal clear, warm and “in the face”, even for the last row of seats.” Luc de Paepe owner Pa-P.A.
After a first demo-session with Alcons QR36 sets equipped with double RBN1801 pro-ribbon HF drivers: two columns in the main ‘national’ nave of the Basilica, one column in the ‘parish’ nave, where it excelled over the existing recently installed beam-steered system in the A/B test, the church management decided to invest in the Alcons system.
Part of the interior, with 60m / 197-ft. with QR36 in the background
“The result of the tests was astonishing and far better than the telephone-sound they had before,” enthuses Luc De Paepe, managing director of Pa.P.A, “And the church administration gave the green light for an Alcons configuration in the national nave. The QR36 was designed for difficult acoustic environments, but the national Basilica became the first church to install a set – contrary to most line array systems (“that still have too much dispersion”) they offer a perfect, almost absolute 3° vertical dispersion angle, projecting the sound right to the church audience.”
With the Basilica’s architect Jos Van den Breeden, the Alcons QR36 speaker enclosures were tailored to fit the monumental architecture, and Alcons’ engineers configured the system from two meter QR36 columns, to obtain the perfect sound for the church. The speakers and custom stands were supplied in a special RAL ‘ancient’ green finish, contrasting with the basilica interior and terracotta-finished pillars.
Each of the QR36 combinations was equipped with an additional Alcons VR8 full range speaker cabinet for out-fill – with large worship services, the VR8’s are used as monitor speakers for the choir and in the side aisles.
The double QR36 with VR8 outfill
Pa-P.A. removed the old and worn speaker system and installed two Alcons QR36 sets serving the whole church – all of the cabling was replaced and incorporated in the church architecture. A mobile control desk, featuring two Alcons ALC2 controller-amplifiers and pre-configured DDP processors; A Soundcraft EPM8 console completes the configuration and provides an easy operable unit.
Luc de Paepe: “the intelligibility over the entire space is remarkable, with a measured STI of 0,7. The full-range 70Hz to 20kHz system response makes the vocals crystal clear, warm and “in the face”, even for the last row of seats; From front to rear, we have a 1dB SPL drop-off in the mid/high frequency band. And the nice part is, the system is very user-friendly, as it doesn’t need any difficult (beam-steering) processing, it’s really “plug and play”! “
Herman Cosijns and Luc de Paepe (L to R)
The system was ‘baptised’ during a celebration for the Belgian army and in a ceremony with Congolese Bishop Monsengwo and stood the test glamorously. And this was the real reason for the renovation of our installation: we as a church attach much importance to God’s word – if one cannot understand this, there’s no reason for gathering in this church,” says Basilica rector Herman Cosijns. “More than the evolution in experiencing religion, with music and choir, the word is crucial. It’s great that we have been able to purchase this equipment with the support an donations of so many in the archbishopric.”
