Abstract: An air induction system for attenuating sound produced by an engine, a housing defining a working chamber for attenuating sound produced by the engine. The air induction system further includes a tube having a first end extending into the working chamber and a second end to be in fluid communication with the engine. The air induction system further includes a first flange radially extending from the tube and disposed in the working chamber. The tube, the housing and the first flange cooperate to define a resonator operable to attenuate sound produced by the engine.

Abstract: A sound enhancing system is disclosed for use with an engine of a vehicle to amplify engine sounds produced by the engine over a predetermined engine RPM operating range. The sound enhancing system includes a sound enhancing component which may be fixedly mounted within an engine compartment so that it does not move relative to the engine as the engine experiences engine roll during changes in engine RPM or a load experienced by the engine. An inlet duct communicates with an inlet of the sound enhancing component and receives air pulsations drawn in by the vehicle's induction system, and is able to vary in length as the engine roll occurs, when engine RPM increases and decreases. This enables a frequency response of the sound enhancing component to be modified in accordance with changing engine RPM or the load experienced by the engine.

Abstract: An air induction system for attenuating sound produced by an engine, a housing defining a working chamber for attenuating sound produced by the engine. The air induction system further includes a tube having a first end extending into the working chamber and a second end to be in fluid communication with the engine. The air induction system further includes a first flange radially extending from the tube and disposed in the working chamber. The tube, the housing and the first flange cooperate to define a resonator operable to attenuate sound produced by the engine.

Abstract: A sound enhancing system is disclosed for use with an engine of a vehicle to amplify engine sounds produced by the engine over a predetermined engine RPM operating range. The sound enhancing system includes a sound enhancing component which may be fixedly mounted within an engine compartment so that it does not move relative to the engine as the engine experiences engine roll during changes in engine RPM or a load experienced by the engine. An inlet duct communicates with an inlet of the sound enhancing component and receives air pulsations drawn in by the vehicle's induction system, and is able to vary in length as the engine roll occurs, when engine RPM increases and decreases. This enables a frequency response of the sound enhancing component to be modified in accordance with changing engine RPM or the load experienced by the engine.

Abstract: A device for transmitting engine sound into an interior of a motor vehicle includes a sound transmission line having a first end in acoustic communication with an air intake tract and a second end arranged to direct engine sound towards the motor vehicle interior. A sound transmitting porous media is arranged in-line with said sound transmission line and restricts airflow wherein the porous media such that airflow in the sound transmission line is required to pass through said porous media.

Abstract: A sound distribution apparatus provides a driver with an audible impression of the operating speed, load and performance of a vehicle engine. The sound distribution apparatus includes an assembly of one or more sound transmission ducts interconnected to conduct or transmit engine sounds from the air intake tract into the passenger compartment and to distribute the sound in a uniform fashion from behind the dashboard at the front to the passenger compartment. The sound distribution duct includes a plurality of sound diffusion apertures arranged on the outer wall, each configured to diffuse a portion of the transmitted sound into the passenger compartment. A sound permeable airflow blockage device seals the sound transmission duct interior in a gas-tight way preventing airflow.

Abstract: A device for transmitting engine sound into an interior of a motor vehicle includes a sound transmission line having a first end in acoustic communication with an air intake tract and a second end arranged to direct engine sound towards the motor vehicle interior. A sound transmitting porous media is arranged in-line with said sound transmission line and restricts airflow wherein the porous media such that airflow in the sound transmission line is required to pass through said porous media.

Abstract: A tuned acoustic attenuation device includes a housing defining a chamber within with air inlet and outlet channels opening into the chamber. An acoustic chamber or chambers are arranged on an exterior wall of or alternately within the housing and positioned to extend in a substantially lateral parallel relationship to the inlet or outlet channel and are configured as quarter wave tuners. The acoustic chambers may be realized within the housing by adapting housing stiffening support ribs of the housing. The acoustic attenuation characteristics of individual acoustic chambers cooperate to broaden the sound attenuation bandwidth or increase the attenuation at selected noise frequencies.