Patent ID: 8634574

Claim:
A device for transmitting engine sound into an interior of a motor vehicle, comprising: a sound transmission line having a first end and a second end, wherein said first end is in acoustic communication with an air intake tract of an engine and said second end is arranged to direct engine sound towards said motor vehicle interior; and a sound transmitting porous media arranged in-line with said sound transmission line and restricting air flow through said sound transmission line, wherein said porous media is arranged to require air flow through said sound transmitting line from said first end to said second end to pass through said porous media; wherein said porous media is configured and adapted to permit passage of said engine sound; wherein said porous media is a media suitable as an air filtration media, said porous media having a porosity suitable to remove particulate contaminants from said air flow in said sound transmission line; wherein a first side of said porous media is air flow and air pressure pulsation communication with airflow in said air intake tract; wherein an opposing second side of said porous media is in airflow communication with said vehicle interior; wherein said porous media is transparent to transmitted sound; wherein said porous media passes air flow between said vehicle interior and said sound transmission line from said second side to said first side of said porous media: wherein said air intake tract includes an air filter element; and wherein said porous media has a total pore area or pore size that provides significantly higher restriction to air flow than is presented by the air filter element such that a major portion of air flow to said engine occurs through said air filter element rather than said porous media.