Abstract: A hollow structure has a hollow body with an annular first space and at least one resonator. In the resonator there is formed an elongated second space with a pair of openings at two ends thereof. Each of the pair of openings opens inwardly toward the interior of the first space. The ratio of the length of a centerline of the second space to the length of a centerline of the first space is within a range of from 0.45 to 0.55. The second space is disposed in a curve along a circumferential surface of the first space and is shaped such that one of the two ends of the second space is folded back toward the other end.

Abstract: A hollow structure has a hollow body with an annular first space and at least one resonator. In the resonator there is formed an elongated second space with a pair of openings at two ends thereof. Each of the pair of openings opens inwardly toward the interior of the first space. The ratio of the length of a centerline of the second space to the length of a centerline of the first space is within a range of from 0.45 to 0.55. The second space is disposed in a curve along a circumferential surface of the first space and is shaped such that one of the two ends of the second space is folded back toward the other end.

Abstract: A headphone includes: a housing; a first driver unit disposed in the housing; a partition wall dividing an internal space of the housing into a first space and a second space, the first space containing the first driver unit; a second driver unit attached to the partition wall; and an acoustic adjustment circuit configured to receive a first signal to be input to the first driver unit and generate a second signal to be input to the second driver unit based on the first signal.

Abstract: A speaker system includes a first panel, a second panel, a third panel, a speaker unit, and a sound absorber. The first panel is an outer panel constituting a part of a vehicle door of a vehicle having a compartment. The second panel constitutes a part of the vehicle door and is situated closer to the compartment than the first panel and has an opening. The third panel constitutes a part of the vehicle door and resides between the first panel and the second panel. The speaker unit overlaps the opening in a plan view when viewed from the compartment along a central axis of the speaker unit and outputs sound toward the compartment. The sound absorber is arranged at a location corresponding to an anti-node of particle velocity in a standing wave generated in a space defined between the speaker unit and the first panel.

Abstract: A sound absorbing apparatus includes a first member including at least one first opening portion for enabling Helmholtz resonance, and a second member that is on the first member, has a plate shape or a sheet shape, and is formed of a porous material. The second member includes at least one second opening portion overlapping one-to-one with the at least one first opening portion in planar view. A periphery of each of the at least one second opening portion coincides with or is located outside a periphery of each corresponding one of the at least one first opening portion in planar view.

Abstract: Disclosed is a speaker system that includes a first panel that is an outer plate of a vehicle door, a second panel that is disposed on a vehicle interior side of the vehicle door, a third panel that is disposed between the first panel and the second panel, a speaker unit that has a sound emitting surface for emitting a sound toward a vehicle interior, and spacers that are disposed between the speaker unit and the third panel.

Abstract: Disclosed is a speaker system that includes a first panel that is an outer plate of a vehicle door, a second panel that is disposed on a vehicle interior side of the vehicle door, a third panel that is disposed between the first panel and the second panel, a speaker unit that has a sound emitting surface for emitting a sound toward a vehicle interior, and spacers that are disposed between the speaker unit and the third panel.

Abstract: A sound absorbing member includes a first end face, a second end face, and a side face. The second end face is opposite to the first end face. The side face is positioned between the first end face and the second end face. The sound absorbing member is insertable into an aperture provided on a plate-like or sheet-like base material. The sound absorbing member has a tubular shape. The first end face includes a first opening. The side face includes at least one second opening.

Abstract: A speaker system includes an outer panel of a vehicle door of a vehicle having a compartment; a panel member that constitutes a part of the vehicle door, the panel member being closer to the compartment than is the outer panel; an inner panel of the vehicle door, the inner panel residing between the outer panel and the panel member to form a first space and a second space, the first space being defined between the panel member and the inner panel, and the second space being defined between the outer panel and the inner panel, wherein the inner panel has a through hole that communicates the first space with the second space; and a speaker mounted to the panel member; wherein: the panel member is mounted to the inner panel; and the panel member together with at least the outer panel constitutes an enclosure for the speaker.

Abstract: A hollow structure has a hollow body with an annular first space and at least one resonator. In the resonator there is formed an elongated second space with a pair of openings at two ends thereof. Each of the pair of openings opens inwardly toward the interior of the first space. The ratio of the length of a centerline of the second space to the length of a centerline of the first space is within a range of from 0.45 to 0.55. The second space is disposed in a curve along a circumferential surface of the first space and is shaped such that one of the two ends of the second space is folded back toward the other end.

Abstract: A speaker system includes a first panel, a second panel, a third panel, a speaker unit, and a sound absorber. The first panel is an outer panel constituting a part of a vehicle door of a vehicle having a compartment. The second panel constitutes a part of the vehicle door and is situated closer to the compartment than the first panel and has an opening. The third panel constitutes a part of the vehicle door and resides between the first panel and the second panel. The speaker unit overlaps the opening in a plan view when viewed from the compartment along a central axis of the speaker unit and outputs sound toward the compartment. The sound absorber is arranged at a location corresponding to an anti-node of particle velocity in a standing wave generated in a space defined between the speaker unit and the first panel.

Abstract: A speaker system includes an outer panel of a vehicle door of a vehicle having a compartment; a panel member that constitutes a part of the vehicle door, the panel member being closer to the compartment than is the outer panel; an inner panel of the vehicle door, the inner panel residing between the outer panel and the panel member to form a first space and a second space, the first space being defined between the panel member and the inner panel, and the second space being defined between the outer panel and the inner panel, wherein the inner panel has a through hole that communicates the first space with the second space; and a speaker mounted to the panel member; wherein: the panel member is mounted to the inner panel; and the panel member together with at least the outer panel constitutes an enclosure for the speaker.

Abstract: A sound absorbing apparatus includes a first member including at least one first opening portion for enabling Helmholtz resonance, and a second member that is on the first member, has a plate shape or a sheet shape, and is formed of a porous material. The second member includes at least one second opening portion overlapping one-to-one with the at least one first opening portion in planar view. A periphery of each of the at least one second opening portion coincides with or is located outside a periphery of each corresponding one of the at least one first opening portion in planar view.

Abstract: An acoustic structure includes: at least one hollow section defined by a pair of opposed transparent or translucent wall members and a plurality of connecting wall members interconnecting the pair of wall members, and at least one opening portion communicating an interior space inside the hollow section to an exterior space. At least some of the connecting wall members may have colorless or colored transparency or translucence. Further, a mirror surface may be provided on any desired portion of the wall members defining the hollow section. Furthermore, a lighting device may be disposed near the outside or inside of the hollow section. Because light or a scene on the opposite side of the acoustic structure is visible through the transparent or translucent wall member, design quality and usability of the acoustic structure can be enhanced.

Abstract: A vehicle sound generation apparatus 20 is constituted by a first pressure sensor 21a, a second pressure sensor 21b, a signal processing section 24 which performs processing of changing pressure signals output from the first pressure sensor 21a and the second pressure sensor 21b in accordance with the operation state of an automobile 10, and speakers 28a, 28b which output, as an intake sound of an engine 12, a sound pressure signal processed by the signal processing section 24. The first pressure sensor 21a is provided on an intake duct 15 connecting an air cleaner 16 and a throttle body 17 at a position between the air cleaner 16 and the center of the intake duct 15, and the second pressure sensor 21b is provided between the engine 12 and the throttle body 17.

Abstract: Provided is a sound generating device (20) for a vehicle, including: a plurality of pressure sensors (21a to 21d) for detecting air pressures of an air intake sound of an engine (12) and outputting the air pressures as sound pressure signals; a signal processing unit (24) for performing processing of changing the sound pressure signals in accordance with a driving condition of a vehicle (10); and loudspeakers (28a and 28b) for outputting the sound pressure signals as the air intake sound of the engine (12). Then, the plurality of pressure sensors (21a to 21d) are provided at an interval in a circumferential direction of an outer periphery of an air intake duct (15) at positions in a vicinity of an air flow meter (18) on an air cleaner (16) side with respect to a center of the air intake duct (15), the air intake duct (15) connecting the air cleaner (16) to a throttle body (17).

Abstract: An acoustic structure, including a pipe having a plurality of cavities that are partitioned by a partition, each of the plurality of cavities extending in a first direction that is a longitudinal direction of the pipe, wherein the pipe has at least one opening which permits the plurality of cavities to communicate with an exterior of the pipe, a position of each of the at least one opening in the first direction being a first position.

Abstract: A vehicle sound generation apparatus 20 is constituted by a first pressure sensor 21a, a second pressure sensor 21b, a signal processing section 24 which performs processing of changing pressure signals output from the first pressure sensor 21a and the second pressure sensor 21b in accordance with the operation state of an automobile 10, and speakers 28a, 28b which output, as an intake sound of an engine 12, a sound pressure signal processed by the signal processing section 24. The first pressure sensor 21a is provided on an intake duct 15 connecting an air cleaner 16 and a throttle body 17 at a position between the air cleaner 16 and the center of the intake duct 15, and the second pressure sensor 21b is provided between the engine 12 and the throttle body 17.

Abstract: Microphones are provided at an air inlet of the engine and a vehicle-cabin-side wall surface of an engine room, and engine sounds are picked up. The engine sound is processed by a signal processing section, and the processed engine sound is output from a speaker provided in a vehicle cabin. The signal processing section is provided with a filter which simulates a sound insulation characteristic of the vehicle cabin and a transformation section for processing the engine sound according to driving condition. A spectrum transformation characteristic of the transformation section is determined according to values detected by a vehicle speed sensor, an engine speed sensor, and an accelerator depression sensor, and a spectrum of the engine sound is transformed by means of specification of the spectrum transformation characteristic, thereby enhancing an engine sound.

Abstract: An acoustic structure (e.g. an acoustic tuning panel) includes a plurality of boards and a plurality of resonance tubes with a plurality of openings. The openings are formed at different positions on the side faces of the resonance tubes. One resonance tube may be interposed in and supported by a pair of boards, or one board may be interposed in and supported by a pair of resonance tubes. The resonance tubes are mutually movable in the axial direction so as to independently adjust the opening area of the opening of the resonance tube. With this behavior, it is possible to adjust a ratio of the opening area of the resonance tube to the sectional area of the internal cavity of the resonance tube, thus adjusting the bandwidth of a band causing a sound-absorbing effect and a sound-scattering effect in an acoustic space (e.g. a sound chamber).