This month, my car lease comes due, and I’ve got a couple options to consider. Fortunately, I received great advice a long time ago on car shopping, when (briefly) working in that industry.
We must keep a wide-open view of our audio decisions, to incorporate our most acute needs, along with a long-term plan for the facility.
Right now, I am not forced into any quick decisions, or feel stuck in a vehicle that’s too big/small for my needs. Thankfully, following some advice about good vehicle planning has panned out. Believe it or not, the same principles apply, when matching loudspeakers to your church.
When it’s time for your next set of wheels, it’s wise to think about our overall transportation needs, and then narrow it down to features that mean the most for our daily commutes and driving adventures. Typical road conditions, fuel efficiency, weather patterns, number of passengers, storage space, power, torque, infotainment system, comfort and many other aspects quickly dominate our thinking.
It’s easy to get confused with so many choices.
In the midst of many purchasing decisions, I’ve found that like many things, keeping the main thing the main thing means a lot, by keeping decisions focused on features, that will have the most value and long-term effect.
Often car shoppers fixate on one key feature (or the price). As a result, they don’t look ahead to their needs long-term and consider how often they will need to change vehicles, to adapt to changing needs, as they transition from one season of life to another.
Selecting audio equipment isn’t much different.
We must keep a wide-open view of our audio decisions, to incorporate our most acute needs, along with a long-term plan for the facility. For this reason, it’s usually best to start any discussion about loudspeaker choices, with some analysis of the acoustics of the facility, where we plan to use amplified sound.
Any changes we do to the facility, to make the natural acoustics more suitable to our intended usage, will pay dividends for decades, even as audio technology changes over time.
It’s a true blessing to be able to use a meeting space for any purpose, with or without the audio system, and enjoy a functional listening experience.
A great loudspeaker system can be a satisfying long-term investment, so long as it’s well coordinated with the acoustic environment within which it’s used.
Consider a multiuse church venue, maybe a “Confresanctecafegymnatorium”-type space that gets used for all sorts of worship, training, sports, and social events. For several years, I was part of a church that had a very basic structure, seating about 300 people, in a drywalled rectangular box. It was used for Sunday worship, banquets, sports and other activities throughout the week.
Thankfully, the ceiling had a perforated metal finish, with fiberglass insulation above the perf deck. This added some sound absorption – but only for sound reflections that occurred at the ceiling surface. The architect had not considered the flutter echoes and midrange energy buildup that would occur along the walls, during events with amplified sound. During athletic events, communication across the room was impeded by reflected sound, especially if there were lots of participants, which added up to lots of noise generation. While highly directional speakers did help with the band, no amount of loudspeaker technology was going to fix the acoustics for all the other types of events.
If your architect has not retained an acoustical consultant, to ensure that the building materials selected are appropriate for speech and music communication, be sure to retain an expert in worship space audio and acoustic design. There are resources available for churches of all budget ranges.
Sometimes calls to loudspeaker manufacturers for support can help quickly identify problematic acoustical features, and outline what can be done about it, from a speaker technology point of view.
Frequently, Community’s Technical Applications Group, now known as Biamp’s Large Venue Group, can point out architectural features that will be problematic for both natural and amplified communication, so you can research your options to address those structures, and recruit the appropriate help. The goal of the group is to integrate sound systems into your venue, that are a good match to your needs, to provide an extraordinary listening experience for the entire congregation, even if the venue acoustics are not ideal.
What can you do to begin getting a grip on just how good/bad the acoustics are in your space?
Let’s be careful to first point out that there’s no such thing as “ideal” acoustics, but rather a range of acceptability for an intended purpose.
When we take acoustic measurements of a venue, most metrics have a minimum performance requirement, but there’s a range of acceptable use above that minimum. The following casual tests help frame up whether a venue needs minor or extreme improvements.
Often you don’t have immediate access to acoustic test equipment. In those cases, how can you quickly assess the acoustics of a space, and determine if they will be detrimental to speech reproduction?
There’s a simple unamplified procedure you can follow, based on EAD, or Equivalent Acoustic Distance.
Presuming you have healthy hearing, in other words having no history of hearing damage, you can evaluate EAD by simply listening to a public speaker - someone with experience speaking to an audience, in the venue, at various distances.
- Begin with the speaker reading an unfamiliar passage of written material, from a position where they would normally stand, i.e., pulpit, platform, etc.
- Listen at a position close enough that their voice dominates the acoustics, such that you have absolutely no problem understanding the words.
- As they read, slowly move away from the speaker, paying close attention to any significant change in clarity. Try listening from various sections where the congregation or audience would be located.
- Once you notice a change about the quality of their voice – especially if you begin to struggle to understand or need to focus slightly more attention – then you’ve likely found the maximum Acoustic Distance of the natural sound of the space. In the design of the sound system, the goal is to raise the intelligibility and sound pressure level, or SPL, of the entire system, to offer the same Equivalent Acoustic Distance at all seats.
It’s important to not force the speaker to change their natural level or cadence, and that the listener should not struggle to hear clearly. You’re looking for the point at which the sound level of the room’s reflections begins to interfere with the speaker’s voice. At this point, if you’re fairly close to the speaker, you know the acoustics need a professional evaluation, and you’ll likely need loudspeakers with high directivity.
If you find that during this test, though, that you can move to positions closer than the farthest seating locations, then the acoustics are more suitable to speech. In both cases, the EAD helps indicate the scale of the sound system needed, and the overall system complexity.
Another test you can make of your current sound system evaluates the Critical Distance. This process helps quickly determine if the sound system in your meeting space is adequately sized to control frequencies needed for speech intelligibility.
To read the second part of this article, titled, "Testing and Design Work Key to Figuring Speaker Needs for Space," which published October 8, check it out here.