Acoustically reflective fabric

Compiled by Juli Case

We’ve got a job where we’ve been asked to use a fabric that is acoustically reflective. What kind of material is that?

Sound waves tend to bounce around an open space. A hanging fabric, such as a banner or fabric sculpture, can disrupt or even absorb that wave; fabric is more traditionally used for sound absorption rather than reflection, although it certainly can be done successfully. A material that is most effective for sound absorption has a lot of fiber on the surface or is porous to allow sound to pass through to a second layer for insulation. For sound reflectance, you want the opposite. No fabric is going to be perfectly reflective, but a tightly woven fabric or a coated one (such as PTFE-coated fiberglass) has a slick, even surface that is most similar to other acoustically reflective materials such as wood or metal. If you want to use a lightweight material, stretching it over a hard surface may improve its reflective characteristics.

Juli Case is IFAI‘s information and technical services manager.