Welcome to the world of Church Acoustics

Diffusers are amazing tools when used properly in a church. They solve a variety of problems in one step. Nothing performs better.

One question that is often asked, can you turn the diffusers sideways?  This is a great question, and the answer is based on our anatomy.  As humans, our ears are on the side of our heads.  This means we get our sound information for direction and clarity of speech on the horizontal plane or side to side. The time difference between our ears give us directional info to identify where a sound is coming from, and for speech, it helps us to focus on someone talking to us.

For diffusers to work correctly and to solve multiple problems in one step, their orientation is critical.  When applied vertically, the diffusers can solve between 10 – 29 acoustical issues in one step. No other acoustical system can do this.

The problems solved or reduced are:

1. standing waves
2. deadspots
3. hotspots
4. eliminate echoes
5. eliminate flutter echoes
6. bass build-up,
7. speech intelligibility,
8. increases the signal to noise ratio up to 25dB throughout the room
9. eliminate or less floor monitor spill,
10. less sound system distortion
11. less bass distortion
12. helps to equalize the bass and mid frequencies
13. gain before feedback,
14. even distribution of sound,
15. elimination of delayed speakers in most cases,
16. better stereo imaging for stereo sounds (when the right equipment is used)
17. higher attention span,
18. makes the room easier for the musicians to perform
19. improved sound for people with hearing aids
20. better congregational singing
21. easier for the sound-person to get an excellent mix
22. it can reduce or eliminate the need for drum shields or both
23. makes the room less fatiguing for the minister to preach
24. fewer to no complaints if the sound system is louder
25. improves the sonic quality of the sound system
26. can add up to an octave of clear bass from the sound system
27. better bass from musical instruments both acoustic and amplified
28. it helps to make the room more relaxing to hear speech and music.
29. lowers the sound levels from HVAC systems

If your church has a pipe organ, you will want to know this. One of the most interesting characteristics we have learned with using this method is that for some churches that want to maintain a longer reverberation time, plus have all of the benefits of better speech quality, the half-round tubes can increase speech intelligibility without changing the reverberation time. No other acoustical system can do that. For churches that have a pipe or electronic organ and want better speech quality, this method allows a church to balance the need for music and speech.

When diffusers are installed horizontally, the list of benefits is much shorter.

1. standing waves,
2. bass build-up,
3. Helps to equalize the bass and mid frequencies
4. It can add up to an octave of clear bass from the sound system and musical instruments.
5. Can only reduce echoes, not eliminate them

There is more to these differences.  Because we have ears on the sides of our heads, the rate of control is exponential when the diffusers are mounted vertically.  One of the principals of how these diffusers work is by phase cancellation, which is the same technique as in noise-canceling headsets.  The more random the sounds are scattered, the more the overall energy is canceled from the physics principle of phase cancellation.  As a result, when mounted vertically, the diffusers can get up to 40dB of energy reductions or absorption by air friction.  When you mount the diffusers horizontally, you will only get about 10dB of the overall reduction.

The reason horizontally mounted tubes are less effective is because you are creating large reflective surfaces on the horizontal plane that reflects enough energy back into the room, which it is adding noise back to the listener that in turn, reduces the signal to noise ratio. This cancels almost all of the benefits of using half round diffusers horizontally.

Here is a simple experiment you can do yourself. Find a round container that is at least 7 to 8 inches round.  You can every use a large cooking pot, planter, or roll up some cardboard.  Now say a bunch of words into the side of the container vertically.  After talking for about 15 seconds, turn the container sideways, and talk for another 15 seconds.

What just happened? Like most people, they notice that when the container was horizontal or sideways, there is a distinct reflection. When you turn the container vertically, the reflection goes away.

This simple experiment demonstrates how powerful the half-round shape is.  In the vertical position, when the half rounds are placed on a wall in groups, you can adjust the spacing between the tubes to determine how much reflection you want, plus shape and equalize the sound at the same time.  This is a compelling way to manage church sound once you understand how effective and simple this system works.

Just as a reminder, for all churches, you have to have a balance between absorption and reflection. The half-round tubes are not always a one and done solution. It has to be part of an integrated system. Typically, for most churches, if you have carpeted floors and padded seating, that is often all the absorption needed. If your church doesn’t have carpet and padded seating, then you will have to add enough absorption to the walls to match what would be on the floor. That is a narrow window to get it just right.

For churches that play their music loud, some people wait in the foyer until the sermon starts or they wear hearing protection during the music portion of the worship service. With the half round system, it allows the sound system to perform 10 to 20dB louder with fewer people needing hearing protection. People turn to hearing protection when there is too much distortion in the sound. A distorted sound is irritating and painful to many. People turn to hearing protection, even when the sound levels are well below 85dBa. When a room is diffused properly with half rounds, it reduces or eliminates bass and mid-range distortion. With distortion out of the way, the sound at 85dBa becomes pleasant and easy to listen to. That pleasantness remains constant over 100dBc. Consider this – in a church with this kind of acoustical system with the right room shape and height, it is common for un-amplified congregational singing to be around 100dBc. When that happens almost no one complains. Why? Because there is no distortion. Half-round diffusers prevent distortion. This transforms any worship space into a music-friendly space at any sound level.

Church acoustics and amplified sound play a significant roll in the health of a church. When sound is good, it helps to grow the congregation. When sound is bad, it gets in the way of providing a clear message, that leads to less attendance which means fewer people tithing. In the end, there is nothing more important than preaching the Gospel in the best clarity possible.

To ultimately answer the question of Aesthetics vs performance, the smart answer is this. When an acoustical system works, people don’t mind how it looks.  If anything, they grow to like it.  When other acoustical systems are used, they often fall short on the expected and promised performance.  As a result, those systems become more like wall furniture and in some cases, artwork.  This drives up the cost of those systems.  Here is the truth most experts and salespeople will never share or admit.  To get the equivalent performance of the half-round tubes as a Do It Yourself project compared to ready-made products, the cost difference is 35 to 1.  A church that fixes their acoustics with cardboard tubes as a DIY including paint and hardware for a 400 seat church may spend $2,000.00 installed.  A ready-made system of equal performance will cost a minimum of 75,000.00 installed.  That is equal to fixing 35 churches of the same size.  Even if the same church buys custom made half-round diffusers, they may spend $20,000.  When compared to other acoustical system costs, that is enough money to fix 3 churches.

There is something to be said about how people react to anything put on the walls.  When people see cloth-covered panels, there is an expectation of good sound.  When that doesn’t happen, people often resign to the notion that the problem is too complicated and too expensive to be properly fixed or that the problem is impossible to fix.  Most people just put up with the problem and accept it as normal and don’t bother with complaining.  That is a lie created by bad information and myths that keep churches from getting the sound they deserve.  Sound excellence is a necessity, not an option.

When an acoustical system works, people don’t mind how it looks.  When it doesn’t work as promised, it has to look amazing.  Do you want a church that looks good and has fewer people attending or a church that is full all the time regardless of how it looks?