It's busy, busy, busy all around you and yet, it stays clear and calm where you are, no matter where you are. Every table is a good table. You are waiting tables and as you move from table to table, it's always busy out there, but the calm seems to follow where ever you go. 

Acoustic Coffered Ceiling - Church

Before the acoustic coffered ceiling was installed, you'd hear someone laughing loudly from somewhere in the room, and you would look up and see them folding over in good humor. Now, you still might notice someone folding over with laughter... but you actually can't even hear them laughing. You just hear a low level hubbub of activity and of course, the people immediately around you. 

When you look up you see raised ceiling panels, but the sound reflects back down to your group, keeping the communication bright and lively. When you look into the distance, the view changes. You no longer see the raised ceiling panels, you only see the sides of the coffered beams. And then next time you sit at a different table, and the same perspective comes into view. Even when you walk around, the bright ceiling just follows you around, like an umbrella. And off in the distance in any direction the ceiling disappears into the color and character of the coffered beam pattern. And so it is with the sound in the space.

Directional Acoustics

Acoustic Coffered Ceiling - Christiansen Great Room

The ASC Coffered Ceiling is a grid of sound absorbing panels which create the architectural effect of a coffered beam ceiling. The Coffered Ceiling system acts two completely different ways on sound, depending on which direction the sound is traveling in the room. Sound traveling across the room runs into the sides of the acoustic panels and is absorbed. Sound traveling vertically in the room runs into the coffer part of the system, the untreated ceiling surface between the acoustic panels and is reflected back down without any attenuation. 

The depth of the acoustic beam and size of the grid size determine the horizontal absorption coefficient and the vertical reflection coefficient. Deep acoustical beams absorb more horizontal sound than shallow beams. Small grids also absorb more horizontal sound than large sized grids. The depth of the acoustic beam has little impact on the vertical reflectivity of the ceiling, but the smaller the coffer beam grid size, the quieter the vertical reflectivity becomes. 

Coffered beam patterns are often but not necessarily square. A square pattern offers the same horizontal absorption in either direction. However, a rectangular coffer beam pattern provides more absorption to sound traveling in the direction of the short beam and less absorption in the direction of the longer beam. 

When rooms are too noisy, because of too many people all talking at one time, many designers recommend to add sound panels to the upper portion of the walls. What this type of solution accomplishes it to not attenuate the horizontal sound as it travels along the room, but only when it hits a wall. Unfortunately, when sound travels the length of the room it only hits a wall after a long time compared to how often sound hits the wall in the narrow direction of the room. This means horizontal sound, end to end is lightly attenuated and side to side is strongly attenuated. 

Acoustic Coffered Ceiling - Taco Time

However, with the acoustic coffered ceiling, end to end sound is highly attenuated while side to side is lightly attenuated. Along the width of the room, everyone is neighboring and hearing each other is expected. But sounds from the opposite end of the room are far from the immediate neighborhood and are not welcomed, and may seem intrusive. 

Sometimes the acoustic beam grid might be in a rectangular form, with wide beam spacing in one direction and less-wide beam spacing in the other. This rectangular coffered beam pattern produces an acoustic ceiling that is strongly absorptive of horizontal sound that travels in the direction parallel to the short beam and less absorptive of sound traveling parallel to the long beams. Not only does the acoustic coffered ceiling provide directional acoustics, separating horizontal from vertical sounds, but it can also adjust the absorption rate, Sabines per foot, in different directions. 

Most acoustic coffered beam patterns are parallel with the walls, however a very interesting effect is developed when the square pattern is set along a 45 degree diagonal. Now instead of rectilinear, we see a wicker basket weave that is very light and fun.