How to manage overpowering bass response, poor coverage, and a lack of sound consistency with proper acoustic design.
Steven Durr & Matt Schlachter · November 6, 2015
Contemporary services have become very common in the new millennium, bringing new technology into the church. Introducing amplifiers, a monitor system, and a high-powered sound system into an acoustical environment designed for choral music has led to many unforeseen issues. Among these issues are an overpowering bass response, poor coverage throughout the seating area, and a lack of consistency in the sound from week to week. One of the most common complaints is that things are “way too loud.”
WALL & PLATFORM RESONANCES
When designing acoustical environments specifically for amplified music, the partitions around the performance platform must be reinforced with multiple layers of varying thickness and density. It is very important to avoid resonances in the walls and platform itself. A simple test for resonances is to strike the surface with the side of your fist and listen. It should be very dead sounding, with little or no resonances in the musical spectrum.
More than likely, the walls will resonate at about the same frequency as the kick drum or bass guitar. If the platform resonates at all, it will directly affect the sound of every instrument on it, especially those with a strong bass presence. The platform composition tends to be more complicated than the walls. Choosing the right material is a challenge because concrete is too dense, and a simple wooden platform will be loud and resonant. There need to be additional layers applied for a neutral-sounding platform.
In addition to wall and platform composition, sound absorption is critical in these spaces. Fabric-covered acoustical panels should be placed around the speaker systems, especially at the ceiling and partitions in close proximity to any speakers.
It’s a common sales pitch to suggest a new digital console or new line array will solve your sound problems. This is false. There are a number of things that have a direct effect on the success on your sound system.
Another trend we are seeing is the hiring of one acoustical consultant to design architectural acoustics and a second sound company to design the sound system. This method is proving to have serious flaws. First and foremost, the acoustic and the sound system must be designed with a shared vision of the end results, as they are directly tied to each other. Both must compliment each other and, if developed separately, will inevitably end with both parties blaming the other for a less than desirable result.
THE SERVICE-FIRST APPROACH
Remember one important thought: No one came to hear your sound system. They came to have an emotional connection with the presenters and with God. Many of today’s audio equipment have a distinct inherent sound, which, unfortunately, is far from neutral. A sound system designer is similar to an artist, and each component should be chosen carefully and with great purpose, much in the same way an artist chooses colors or brush sizes. The sum of these components should produce a warm, natural sound that compliments the room’s natural acoustics. The intent is for the sound system to “disappear” from the service.
The wealth of features in digital technology available to the sound person is breeding a poverty of skills and, in turn, negatively affecting the emotional aspect of the services. Modern technology has given whoever is running the sound an opportunity to create a caricature of his/her reference point of what the service should sound like. More often than not, this is a dangerous situation as the caricature is nothing like the actual sound of the presentation. When a properly designed environment is being operated correctly, there should not be any evidence of loud speakers at all. It should be a direct emotional connection between the presenter and the congregation.
STEVEN DURR is president and principal designer of Steven Durr Designs LLC (stevendurr.com), full-service professional design firm, specializing in architectural acoustics, audio system design, and integration design. MATT SCHLACHTER is an associate at Steven Durr Designs LLC.