Types of Acoustic Performance

The 9Wood Products offer two distinct types of acoustic treatment: Absorption or Diffusion. In blending science and art for room acoustics, nothing compares with the expert advice of an acoustical engineer. Our goal is to provide wood surfaces that bridge allow the design professional's intent to be met while acheiving the consultant's recommendations.

Consistent with good acoustics is employing the ceiling correct surface to tonally compliment the sound performance of a space. The wrong material, such as metal, can impart a "tinny" or "metallic" signature to the sound. Plastic and fiberglass tend to be "drummy." On the other hand, wood is acoustically warm and organic — one reason acoustic instruments are normally made from wood.


Wood surfaces are naturally reflective with an NRC (Noise Reduction Coefficient) of .05-.15. Absorbtion may be desireable in spaces where acoustic energy would have a negative impact on occupants (education and healthcare settings, for example).

High levels of sound absorption (NRCs of .65–.90) can be economically achieved by means of strategically placing openings in the ceiling, allowing acoustic energy to be passed through the ceiling into acoustically absorbative material hidden in the plenum.

Perforations, reveals or grooves allow for a percentage of sound energy to pass through the wood ceiling and be absorbed by fiberglass acoustic backing material. In general, the thicker the fiberglass backing (3-6# density, 1" to 6" thick) the greater absorption will be achieved, especially at problematic lower (bass) frequencies.

Our Perforated Wood Tile and Acoustic Plank products create tuned resonant sound absorbers. This means they provide peak absorption at certain problematic (typically mid-range) frequencies. These products can acheive NRC ratings of up to .90 NRC.

Because absorption is directly related to the percentage of open area in the ceiling, our Grill and Linear products can acheive the highest NRC ratings.


Diffusion, the scattering of reflected sound, can be achieved by means of a Wood Wave Tile (a curved surface) or scattered by means of irregular surfaces like wood grilles or cubes.

Diffusion can be highly desirable in spaces where the space needs to be more "live," but problems with echo, ring and "slap" need to be avoided. Performance arts halls, houses of worship and lecture spaces are often served well be acoustic diffusion.

Whole-Space Performance

Often a space will need a careful combination of absorption and diffusion to function as it should. By offering a variety of beautiful wood products that can offer either absorption or diffusion, we strive to leave as many design options available to architect as possible.


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