I know what you’re thinking: An article about acoustics, this is going to be riveting…
I know, I know, talking about acoustics isn’t the most exciting thing in the world, but having worked with churches across the U.S. for nearly a decade now, I can with 100 percent confidence say that the biggest non-spiritual factor between engaged and disengaged audiences in the church today, is bad acoustics.
For most churches, poor acoustics means a room that is too reverberant. When reverberation times grow, intelligibility decreases, and so does engagement.
For worship, a lack of intelligibility means even a small band and a few vocals sound unclear and joining with them in song can be quite challenging.
For the 30 to 45 minutes of your service, where a single voice is communicating the message of the Gospel, clarity and a distraction-free environment is the most important thing you can provide those who listen. A reverberant room is neither of those.
It’s not just overly reverberant rooms, though, that kill engagement. It may be hard to imagine how a room that’s too absorptive can be a detriment to engaging people, but it can.
This weekend my family and I went to a movie, and in an empty room 15 minutes before the movie started, I still found myself talking quietly to my family. The room is designed to have low reverberance, and by nature, it makes you want to tone down engagement. Contrast that with a popular restaurant, and how loud and vibrant that feels, and how much that energy draws you into talking with people around you.
Engagement and room energy don’t happen by accident, it takes intentionality and a great balance of absorption and reflection to balance energy and intelligibility.
Trying to get into how to specifically solve each problem, and at what frequency, in a short article would be tricky, but let’s talk generally about what materials help create which effect, and how to create a balanced approach to maximizing both energy and intelligibility.
Acoustical absorption comes in all shapes and sizes, and even a variety of materials. Most materials that have a soft feel to them, have some absorptive value. We’ve all seen the standard 4 foot-by-4 foot square, or 4 foot-by-8 foot rectangle that has a fabric covered frame that is filled with a specific thickness of acoustical foam, and of course many acoustical ceiling tiles provide absorption as well.
A lot of other absorption, though, can find its way into your worship space in less obvious ways. Padded chairs provide absorption, as does theatrical fabric/drapes on your stage or side walls. And of course, people are great acoustical absorption as well!
The key to successful acoustic absorption, though, is knowing what your problems areas are and making sure your materials address those without negatively impacting areas that are already fine, or over-deadening your room.
It’s rare that rooms are equally reverberant across all frequencies, so before you start plastering absorption everywhere, you want to get good measurements or models of your room to know exactly what needs to be addressed.
The lower the frequency that needs to be addressed, the thicker the material should be. If sub-bass frequencies are your key problem, your absorption needs to be at least 4 inches thick to make much of an impact. For low-mid frequencies, 2 inches of thickness will make a real impact. And once you get into 5,000 Hz and above, a thick theatrical fabric will impact your space greatly.
Strategically locating the right materials into the right areas will keep your reverberation times from negatively impacting your worship experience.
The first time I met Pastor Chuck, the worship pastor at a large church in Minnesota, he told me their most important instrument in worship was the congregational voice. That has always stuck with me and is an important consideration when you’re talking about acoustics for a worship space.
While few churches want their speaker system reverberating around the room, many highly value the ability to hear the congregational voice, and that requires a level of strategic reflection in the room.
Reverberation can be created through specific acoustical ceiling tiles, or more aesthetically pleasing “clouds” made from solid surfaces you see in many worship spaces today. These reflective surfaces, strategically located over seating sections, and usually angled slightly away from the speaker system, can help the congregation hear each other and engage more in singing without hurting the overall intelligibility of the room.
Finally, many rooms end up with parallel surfaces that create flutter echoes back and forth in the room. When absorption could end up deadening the room too much, but the echo needs to be dealt with, diffusion is a great way to disperse those reflections without deadening the room. It’s also a great option when you want some ceiling reflection down for your congregational voice, but don’t want the reflections to be too localized.
The combination of reflection and diffusion can help create an atmosphere of warmth and engagement without people specifically hearing themselves. Diffusion, much like reflection materials, is generally created with solid, reflective surfaces. The difference on diffusion is those surfaces are generally curved or multiangled to reflect sound in multiple directions.
The Right Choice For You
I highly recommend partnering with a consultant who can help you get your acoustics right for you.
There are lots of variables to account for, such as the architectural shape(s) of your space, the materials it’s made from, what type of seats you have, etc.
There’s also the vision side of things, the target you want to hit for engagement and how that translates into absorption versus reflection.
While you may want to keep horizontal reflections down in the room from sources like your speaker system, you may highly value congregational singing like Pastor Chuck and need to complement absorptive walls with some reflective ceilings.
Regardless of what your target is, know that engagement starts way before technology with great acoustics, and if you don’t get that right, there is little technology can do, to overcome it.