Abstract: This invention involves a novel implementation of a double-tuned bandpass enclosure installed in a motor vehicle. The enclosure contains a woofer or subwoofer emitting sound through a pair of extended ports to two discrete points of acoustic termination. The enclosure includes a primary and a secondary through-hole, in which the primary through-hole originates from a front chamber and secondary originates from a rear chamber. The first through-hole is connected to an elongated port which transmits a portion of the sound into the vehicle passenger compartment at a primary location. A second elongated port is coupled to the secondary through-hole, which transmits a portion of the sound to a second location, separate from the first. The sound emitted at the two locations represent different but complementary frequency responses, thereby creating a quasi-stereo environment.

Abstract: A compact audio woofer arrangement for a motor vehicle includes an enclosure installed in the motor vehicle. The enclosure contains a woofer or subwoofer emitting a sound. The enclosure includes a primary and secondary through-hole. The primary through-hole allows the woofer to interface with the interior of the vehicle and provides sound directly from the enclosure into a passenger compartment at the primary location. A extended vent acting as an acoustic transmission line is coupled to the second through-hole. The vent transmits sound from the enclosure to a secondary location remote from the primary location, such that the sound is emitted into the adjacent passenger compartment. The primary and secondary acoustic outputs differ by physical location in the motor vehicle, and also by frequency response of the emitted sound, thereby emulating a quasi-stereo environment.

Abstract: A motor vehicle includes headphones having two speakers. The headphones are selectively retained by the seat of the motor vehicle or worn by a human passenger of the motor vehicle. An audio source is communicatively coupled to the headphones and provides audio content to the headphones. A characteristic of the audio content as received by the speakers is dependent upon whether the headphones are being retained by the seat or worn by the passenger.

Abstract: The present invention includes a method of and apparatus for optimizing the reproduction by an audio system of audio source content. The method includes the process of determining the configuration of the audio system and the process of determining the format of the audio source content. Mixing parameters are determined dependent at least in part upon the configuration of the audio system and the format of the audio content. The mixing parameters are applied to the audio source content to create mixed signals optimized for reproducing the particular audio format on the audio system.