Stealth Acoustics in Mount Vernon, Wash., is a manufacturer of aesthetic and unique audio-visual solutions that use “hidden” technologies--making its speakers totally invisible. This is something that is welcomed by many industries, including churches, and is why its invisible speakers have been an unequivocal success, according to the company.
One thing Stealth Acoustics is an expert on is how different elements in a room impact the space acoustically, and that’s especially important in a worship facility, where the message must be heard.
Some Basics
“Sanctuaries are large rooms acoustically, and usually incorporate a certain amount of reverb (the persistence of sound after a sound is produced) that has to be understood and ideally managed,” says Steve Olszewski, vice president of Stealth Acoustics. “The better an acoustical space is natively, the [better the experience will be] for the listener.”
That could mean the unamplified spoken word being more intelligible to less noise bouncing around the church.
“Acoustic mitigation is part and [parcel of the] design goals of anyone who designs a church,” Olszewski says. “Audio always comes into play, and it’s important to consider absorption and diffraction, regardless of what you put in.”
Understanding Acoustics
The art of acoustics, which Stealth Acoustics has reportedly perfected over the years--involves properly choosing the appropriate speakers for a space to put sound where it needs to go for listeners, and to do things to avoid where it doesn’t need to go due to reverb and interference. It’s all about better managing the distribution of sound.
Hard reflective surfaces and parallel surfaces are two of the biggest things that those working on a church’s acoustics must consider. Some house of worship clients may think that simply putting cushions on pews is fine for absorption, and while that might work when the church is empty, as soon as people are inside and sitting down, that won’t work.
Olszewski compares room acoustics to a game of pool, where the angle of reflection is equal to the angle of incidence.
“If sound is coming out of a speaker, and it hits a hard surface at a certain angle, it’s going to bounce off the hard surface at an equal angle and come back to the space,” he says. “It will bounce around and bounce around and bounce around. That does two things—it leads to feedback (the ringing sound), and it loads up the energy in the room and energizes the reverberation space. You want to avoid that as much as possible.”
With a parallel wall, sound hits it and bounces back. High frequencies are easy to absorb but if you use diffusion, it would scatter the sound around. The best thing to do is to use a combination of absorption, diffusion and even reflection.
“Balance the room so it isn’t too ‘live.’ You don’t want people to walk in and it’s too quiet and not natural, with all the oxygen is sucked out of it,” Olszewski notes. “Balance the treatment with proper geometry and surface coverings to reach an optimal balance.”
One tip he gives is if a space has two parallel hard surfaces, only one needs to be treated, because like in the game of ping pong, if you only have ping--the game is over.
“One trick that’s done often is putting absorption panels on both walls, but staggering them so they are opposite of the other wall. Now, you’re not just treating one wall, but balancing everything on both sides,” he adds.
