NEW CHALLENGES, NEW SOLUTIONS
Article kindly provided by Worship-AVL-Asia. Article by Richard Lawn.
The development of Hong Kong’s Yan Fook Church goes hand-in-hand with the A/V technology it uses, as Richard Lawn explains
Upon entering the main sanctuary located on the 19th level, it is easy to see how the room’s dimensions and layout had always posed a problem for the church engineers. The central focal point of the main stage and altar draws an audience of 1,800 seated in the lower stalls and upper balcony levels, which are fanned out over 160-degrees, with some obstructed by large, vertical concrete columns.
Acoustically, however, the room has been well designed with a good choice of wooden materials, absorbers and baffles, while the acoustic walls act as diffusers having being sprayed with acoustic foam. There are no fewer than 11 employees devoting their time to the church’s A/V, broadcast, postproduction, periodical publishing and website management activities. Among them are A/V engineer Lo Koon Shing and A/V consultant Cyril Lam, both of whom are highly experienced technicians having worked for over 11 years at Hong Kong TV broadcaster TVB before coming to work for the church following its relocation to Cheung Sha Wan Road. The pair continually monitor the selection of A/V equipment required to satisfy the dynamic needs of the church, and to date there has been no single, disruptive upgrade as they prefer to integrate new technologies on a continual basis. The new PA system is a testament to this approach, having been slowly introduced over a two year period. The previous horn-loaded system was designed to deliver more traditional services that relied on sermons, prayers and speech. In contrast, the current system favours live music, combining line array and point source elements. Before this new solution was
selected, however, audio specialist
Patrick Shek – a veteran of Hong microphones including an Earthworks QTC40. Using megaphones, the delays and SPL coverage could be calculated at various frequency responses. The results dictated that three different systems would need to be combined to cover the central stalls, outer sections of the stalls and the upper balcony seats.
The upper floor is catered for by eight L-Acoustics Karai modular line source elements, installed in May 2011 and configured in two L-R
four-per-side hangs suspended from overhead trussing. Operating within a 55Hz to 20kHz frequency bandwidth, the response has been lowered down to 32Hz by adding two SB18 subwoofers below the stage. Driven by LA8 amplifiers, each Karai element combines dual 8-inch LF woofers with a 3-inch driver coupled to a Dosc waveguide within a bass reflex tuned enclosure.
The side-fills of the main Sanctuary are served by six L-Acoustics Kiva. Two pole mounted 115XT HiQ coaxial speakers combined with SB15
subwoofers have been placed on the stage for covering the central seats in the downstairs Sanctuary. The two-way speakers, which are powered by LA4 amplifiers, combine a 3-inch compression driver loaded onto a constant directivity conical waveguide in a coaxial configuration with a 15- inch LF woofer.