Owens Corning 705 Rigid Fiberglass Board, 2 inch, Case of 6 Owens Corning 705 is probably the most popular material for acoustic absorption. It is typically covered with fabric and mounted on the walls in a studio, control room, or listening room. Has a NRC rating of 0.95 out of 1. Density is 6 pounds per cubic foot. Product dimensions are 24x48x2 inch panels.