Perforated cellular sound absorption material

A perforated cellular sound absorption material comprising:

• a perforated cellular foam material;
• the perforations having an average diameter no greater than about 0.25 inches;
• the perforated cellular material having a density of less than about 2.0 pounds/ft.sup.3 ;
• the perforated cellular material having an average normal incidence sound absorption coefficient for a selected frequency range between 0 Hertz and 10,000 Hertz greater than an initial average normal incidence sound absorption coefficient of the cellular material for the selected frequency range prior to the formation of the perforations in the cellular material;
• and
• the cellular material having an initial baseline airflow resistance in excess of 5000 Rayls prior to the formation of the perforations;
• and the perforated cellular material having an airflow resistance less than the initial baseline airflow resistance of the cellular material prior to the formation of the perforations.