1. A method for making a multilayer sound absorptive composite comprising:
a) providing a stack of layers comprising in order an air-impermeable barrier, an air-permeable reinforcing core comprising
a foam and having an airflow resistance of at least about 100 miks Rayls and a thickness at least about ⅓ the final composite
thickness, an air-permeable open cell foam or fibrous pad having an airflow resistance less than about 2000 miks Rayls and
a thickness at least about 1/10 the final composite thickness, and a semipermeable airflow-resistive membrane having an airflow
resistance of about 500 to about 4000 miks Rayls, and
b) laminating the stack of layers together under sufficient heat and pressure to form a unitary sound absorptive multilayer
composite.
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