Igreja Batista Central (IBC) is one of the biggest churches in Brasil. The architectural project for the headquarters of IBC in Belo Horizonte was designed to seat 2,500 people in the main room, occupying a total space of 22,900 sq. ft.
The perfect acoustical environment was required from IBC as an important issue for the room, where they wanted to have different performances as worship, concerts, dramas, and outreach events. WSDG was chosen to develop all of the acoustical design and construction of the new facility.
It is a beautiful large fan-shaped concrete building which also includes a parking lot, lounges, administrative areas, children’s educational wing, restrooms and restaurant. Located in a residential area, it was necessary to isolate the auditorium from the buildings around.
Architecture & Acoustics
The large fan-shaped plan was conceited to keep a close visibility and integration between each seat in the audience and the stage. In the other hand, it represented a tough challenge for the internal acoustic treatments.
Acoustical measurements were performed to obtain an understanding of the acoustic and intelligibility characteristics of the existing worship space. Reverberation Times of over 5 seconds were present at mid and high frequencies. The Goal curves for the given room volume call for average reverberation times of around 1.5 to 2.0 seconds for better intelligibility in the room.
In a way to provide a space with a perfect acoustics quality and keep the interior design concept, WSDG used different acoustics treatments. The room received numerous sound baffles suspended above the ceiling structure at the balcony, to control the low frequencies. All way around the front wall of the balcony was created a white diffuser sloped up to avoid the first reflections on the stage. The entire rear concave wall behind the audience was covered with mid-high frequencies absorption panels and membrane resonators to control low frequencies. The entire stage wall received a broad-band acoustic treatment for low, mid and high frequencies. This treatment was covered with an acoustically transparent fabric for aesthetical reasons and was also used to hide all the lighting and air conditioning elements above the stage. The positions of the suspended speakers were adjusted for best sound coverage and proper frequency response throughout the audience.
The facility is equipped with 2 line arrays and 4 subwoofers Electro-Voice, Avion system for the stage musicians and 1 digital console Yamaha.