How acoustics work in a room is often confusing or misunderstood. On this page we describe some issues and outline our approach to making bad sounding rooms sound great!
Acoustical issues in many sanctuaries include:
1) The shape of the sanctuary dictates a wide variety of issues. Fan shape, square (especially orientated on a diamond) or rectangle shaped rooms all have unique but predictable problems. Round or oval rooms are particularly problematic and ideally should not be used for sanctuaries. Historically the best sounding rooms are rectangular or of a show box design.
2) Ceiling designs that are flat or worse, that get shorter towards the back, have more reflection issues than rooms that have peaked or vaulted ceilings.
3) The HVAC system is often poorly designed for the worship space. This contributes to a high level of noise that must be overcome by the presenters and/or the sound system. Ideally the best HVAC should not be heard.
4) Balcony faces often are curved inwards. They act like a parabolic dish focusing energy directly back at the pulpit. This combined with a back wall reflection often means that one of the highest sound levels in the room is right at the pulpit! This minimizes the amount of gain before feedback available at the pulpit microphone(s).
Acoustical Fundamentals
The listenable frequency spectrum is typically considered as 20 - 20,000 (20K) Hz. As you get older the higher frequency range is difficult to hear. Hearing aid professionals will only check hearing up to 8,000 Hz. The foundational, most powerful frequencies are considered the fundamentals. Fundamental frequencies range up to around 800 Hz. Just like a musical instrument, harmonic frequencies are excited or respond to the lower fundamental frequencies. If you play a note on a piano you hear the fundamental of the note you have played along with a complex groupings of harmonics. If the fundamental is out of control it will excite the higher harmonics which makes the overall room louder and unclear.
A frequency has a physical size. We also refer to this as a wavelength. For example the frequency of 1000 Hz (!KHz) is about 13 inches (33 cm) long but 100 Hz is 11 feet (threeish plus metres) long! Low frequencies are more powerful and harder to calm down. It's sort of like dealing with a football player and a ballerina: they each have to be handled in a special way.
Your sanctuary shape and size, as in any room, determines which frequencies are problematic. Sound energy travels throughout the room and bounces off walls and / or ceilings. This creates echoes or reflections. Acoustical issues are very frequency dependent.
It is common in sanctuaries that have padded seating and carpet that some form of absorptive wall panels are added to deal with an audible issue. Using absorption alone does not impact the lower frequencies to any significant degree. This is generally where all the problems are. By reducing the required fundamental frequencies everything becomes much more balanced and controlled.. These are long and powerful wavelengths that combine together to make a wave front.
In addition standing waves are wavelengths or frequency that physically fit within a space in the room. Standing waves will repetitively travel back and forth within the same space creating a resonance issue.
In comparison to absorption, diffusion doesn't just absorb sound waves but it also scatters them. This redirects problem reflections and minimizes them, while at the same time leaving a natural sound in the space. This occurs at all frequencies, especially in the bass, fundamental frequency range, which is harder to control and reduce or attenuate.
There are numerous forms of diffusion available and most are more costly than absorption. CS Acoustics uses a diffusion system that uses multiple units in tandem with each other and the surrounding surface. As a result we are able to use a much smaller surface area foot print than absorption panels and yield a greater amount of reduction at a competitive price.
Impact
By adding the correct wall or ceiling treatment, standing waves and strong low frequency wave fronts are broken down. This stops the cycle of fundamental frequencies being free to resonate repetitively. By reducing the strength of these frequencies, the overall or ambient level in the room is also reduced and more agreeable. The harmonic frequencies are now no longer also affected by out of control, longer, bass frequencies.
The end result of this is a space that is quieter overall and communication, both musical and spoken, is crisp and clear.
What we can do for you.
We can assess your room and suggest applications of just the right amount of acoustical treatment for your room’s needs. Incorporating these applications will dramatically change the character and nature of your space resulting in an opportunity to create more expressive and creative events. Your congregation / attendees will sit back and enjoy the sound and words without leaving fatigued or stressed.
This more complete approach to managing your room acoustically creates a cleaner, increased bass and more articulate speech throughout the entire room. In addition demands on your sound system will be reduced. In some cases funds will no longer be required for new or upgraded sound equipment.
We would be delighted to help you realize how balanced acoustics in your sanctuary can radically impact the effectiveness and enjoyment of attending services and events.
Innovative Acoustical Solutions