Sonic Barrier 1/2 Acoustic Foam w/PSA 18 x 24 The Sonic Barrier 1/2" acoustic damping foam is a precisely engineered material that offers optimum absorption for its thickness The material features our exclusive embossed surface finish that helps to trap acoustic energy and improve high frequency performance A very aggressive pressure sensitive adhesive provides easy and permanent installation onto any surface The Sonic Barrier 1/2" foam is excellent for use in small loudspeaker projects, where bulky damping materials are not feasible This can reduce unwanted sound reflections and prevent them from exiting through the cone or port