Religion may still have many mysteries but sanctuary sound is no longer one of them. Anyone looking for information about sound systems intended specifically for use in houses of worship (HOW) won’t have to look very far or hard these days—bespoke websites aim directly at church users while more generic online systems sellers have optimized their SEO to attract HOW visitors. AV systems integrators highlight religious-venue systems installations in case studies on their websites, while audio equipment manufacturers have set up dedicated departments that focus solely on the HOW market. Church technical directors routinely debate point-source-vs.-line-array solutions over coffee.
"the bottom line is that good communication, between everyone involved, is the foundation for any sound system project."
—GARY ZANDSTRA, Director of Sales & Marketing, Parkway Electric, Holland, MI.
The world of church sound has changed dramatically since Jim Brown of Audio Systems Group Inc. in Chicago offered his 1998 manifesto “Why Churches Buy Three Sound Systems, and How You Can Buy Only One,” a narrative of the times about how churches too often followed ill-suited advice or made decisions based solely on cost. Today, it seems as though you could rack up a B.Sc. degree in a few days’ worth of online research.The real problem, however, might be one that’s become endemic in the age of information—there’s just too much of it out there, and making sense of it in preparation for choosing, designing and installing a new audio system could also result in some badly misspent church funds. What’s emerging as a countermeasure is the increased and more efficient use of collaboration amongst all of the stakeholders involved in designing, purchasing and installing a new or updated sound system in a house of worship. These include the church’s own representatives, the AV systems integrator and any consultants (any of whom might also have the title of system designer), the architect, and the general contractor (GC). It’s a measure-twice, cut-once approach that puts a lot of emphasis on the front end of a project and demands adherence to scheduled collaborative sessions along the way, but the outcomes tend to be much better.
An Uncompromised Approach
“Modern worship builds are rich with audio and video media, and the technology infrastructure considerations are significant. It is more efficient to do the job once in the beginning, as opposed to triaging it later,” observes Dan Palmer, head of integration at L-Acoustics with U.S. offices in Oxnard, Calif. “Unfortunately, we quite often see compromises that are made early which then require change orders or renovations later to get it right.” Gary Zandstra, the director of sales & marketing at Parkway Electric, an AV systems integrator with offices in Holland, Mich., and Loveland, Colo., says he’s very recently embraced Integrated Project Delivery (IPD), a protocol developed by the [Washington, D.C.-based] American Institute of Architects (AIA) that “integrates people, systems, business structures and practices into a process that collaboratively harnesses the talents and insights of all participants to optimize project results, increase value to the owner, reduce waste, and maximize efficiency through all phases of design, fabrication, and construction,” according to the AIA’s IPD webpage. What it really means, says Zandstra, is getting everyone involved together early on and developing a process collaboratively.“Even small deviations from a plan can have substantial effects on other stakeholders’ parts of the plan,” he says. “For example, if a decision is made to change the kind of speakers a system design is using, that will likely require a change in the fly point. That, in turn, requires the input of the architect and the GC.” In other words, under the aegis of IPD, no agent in the process operates unilaterally or in a separate silo; everyone’s actions are transparent to everyone else.Zandstra says the first project he applied IPD to, a large church in Chicago, began with everyone flying in for three days of intensive meetings that resulted in a detailed plan for the church’s sound system. This is not going to be economically feasible for every situation, but using telepresence technologies like Skype and Vidyo can accomplish many of the same goals. Technologies that allow the exchange of documents such as blueprints and other drawings are preferred, because a picture is indeed worth a thousand words—and in the case of a large sound system, possibly thousands of dollars, too.“The bottom line is that good communication, between everyone involved, is the foundation for any sound system project,” says Zandstra.
Types of Sound Systems
Two types of sound systems predominate in the HOW sector: point source and line arrays. The two types are fundamentally different: point source loudspeaker enclosures are usually designed so that all the drivers function as a single source. These systems generally have a fairly shallow coverage range and, as the distance from the source increases, their SPL decreases. Point source sound systems are often used to good effect in rooms that have irregular shapes, such as multiple balconies, at which individual speaker elements can be aimed. A line array, on the other hand, is typically very large in the vertical dimension and is made up of a number of usually identical loudspeaker elements mounted in a line and fed in phase. The distance between adjacent drivers is close enough that they constructively interfere with each other to send sound waves farther than traditional horn-loaded loudspeakers, and with a more evenly distributed sound output pattern. However, line arrays can’t reach well into nooks, so fill speakers are often prescribed for those areas.The line array has emerged as the most popular sound system type in recent years, thanks to its ability to direct sound. That’s being increasingly narrowed down to steerable arrays, which use digital signal processing (DSP) to allow extremely precise aiming of speakers at audience seating and away from reflective surfaces such as hard walls, glass and flooring that can create reflections that mar speech intelligibility. These are especially appropriate for environments such as cathedrals where reverberation is often the biggest acoustical challenge.
An example of how a steerable array solved a problem for one church can be found at First Presbyterian Church in Grand Haven, Mich., whose 350-seat sanctuary recently began hosting separate Sunday services using both traditional music with organ, piano and choir, and a contemporary music service with an electrified band. The existing PA system was no match for the louder music, but the church’s budget committee was divided on the idea of using absorptive treatment to manage the additional acoustical energy from a new, louder PA system, with the committee’s traditionalists concerned that treatments would negatively impact the sanctuary’s natural reverberant sound that suited the choir so well. The church’s AV systems integrator, LiveSpace, a Grand Rapids, Mich.-based AVL integrator, recommended and installed an L-Acoustics ARCS WiFo sound system. They chose specific components based on their dispersion patterns, using ARCS Wide enclosures to maintain a precise 15-degree coverage pattern for the main seating area and an ARCS Focus with 30 degrees of coverage on the choir. “When L-Acoustics says the pattern is 15 degrees, it’s exactly 15 degrees,” says AJ Sweeney, LiveSpace’s director of integration operations and design.
“That’s how sharp the coverage line can be drawn.”
—JOHN STORYK, architect + acoustician, Highland, N.Y.’s Walters-Storyk Design Group.
“That’s how sharp the coverage line can be drawn.”John Storyk, an architect and acoustician with Highland, N.Y.’s Walters-Storyk Design Group who has designed sound systems for a number of large- and mid-sized churches, says steerable arrays have become popular with architects, in part because they can keep sound off of the reflective surfaces that many of them still want to or have to use for structural or aesthetic reasons, and in part because, he admits, “they look cool,” their curvilinear form factors fitting in especially well in contemporary architectural designs and their compactness helping to hide them when that’s preferred. However, steerable line arrays are not a magic bullet. Their design and installation calls for precise pre-measurement of the space using ray-tracing and other software that will establish exactly where sound should and should not be aimed. In addition, steerable-beam sound systems may also raise certain sonic issues. “A steerable-beam speaker will often have less sound pressure level (SPL) capability than a more conventional speaker, and you will precisely steer sound sometimes at the expense of the quality of that sound,” says Zandstra. “I’ll use steerable arrays only when I have to.”Much of sound system design is based on predictive modeling, using algorithmic virtual simulators like Enhanced Acoustic Simulator for Engineers (EASE), which will predict a given space’s acoustical characteristics such as reflection angles. Acousticians also use programs to determine a space’s reverb decay time, known as RT60 value, and the Speech Intelligibility Index, a scale created by the Acoustical Society of America (ASA) in Melville, N.Y., to measure the coherence of the spoken word in various reverberant environments. But Storyk also mentions the auralization process, another algorithmic modeling proposition, but one that’s more accessible to non-professional ears. Defined as “the process of simulating and making audible the effects of playing a known reference sound, such as program material, through a defined loudspeaker system in a particular space,” auralization will let listeners preview how a specific speaker will sound in a specific space. “Our clients can’t read a graph, nor should they be expected to,” says Storyk. “But they can listen and get an accurate sense of what a system might sound like.” Auralization costs run between $5,000 and $10,000, according to Storyk; thus, their value increases as the overall cost of the sound system increases.
A Matter of Aesthetics … and Sensibility
The shift to steerable arrays is one more reason that architects, contractors and systems designers need to be brought together, says Rik Kirby, vice president of sales & marketing at loudspeaker manufacturer Renkus-Heinz in Foothill Ranch, Calif. “Once you realize you have some flexibility with speaker placement, because the DSP allows you to ‘tune’ the arrays within the space by directing the sound, you enter a negotiation process between acoustical performance and aesthetics,” he explains. “The speakers will impact the look of the room but the room also impacts the sound of the speakers, which means they may need to be moved to accommodate that, which could then change the look. You have to have this hashed out before you starting driving screws.”In fact, Kirby and others stress that the collaborative process should begin as early as possible, and that it include as many hats as possible, from architects to systems designers, acousticians general contractors and church committee members, and that the overarching goal be to arrive at an agreed-upon end result that exists on paper (or on a screen) before a foundation is poured for design-build structures or the studs are reached for renovations. “Everyone has to understand what they want the room to do,” he closes. “That’s not easy when the lead pastor wants to make sure that his voice reaches the back of the room intelligibly and the worship pastor wants to make sure the band’s volume won’t be constricted. Make sure you cover all of those bases early on, because failing to do so accurately is the leading cause of dissatisfaction later.”
