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: An acoustic structure includes plate members defining a plurality of hollow regions in parallel relation to each other. Opening portions are formed in one surface (reflective surface) of the plate members in corresponding relation to the hollow regions and in such a manner as to communicate the hollow regions with an external surface. A plurality of sound absorbing members are provided in a dispersed fashion on regions of the one surface (reflective surface) other than the opening portions and neighborhoods of the opening portions. As a modification, a sound absorbing member may be loaded in one of the hollow regions and partly exposed to the outer space through the corresponding opening portion.

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: 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: Wall partitioning between outside and inside of a room has an opening portion closed with a film. Sound insulating plate, comprising a lamination of a sound reflecting plate and a sound absorbing member, is supported in opposed relation to the opening portion and at an interval from the opening portion. Sound transmitted from outside of the room into the room through the film is reflected from the sound reflecting plate and then diffracted via sides of the interval, defined between the sound reflecting plate and the wall, to behind the reflecting plate to reach a human listener. Thus, with a mechanical construction, sound, propagated from outside the room into the room, can be made to be heard as sound of frequency characteristics desired by a human listener present in the room.

Abstract: In an acoustic structure, sound absorbing effect is achieved by interference between incident waves falling in an opening portion and reflected waves radiated from the opening as a result of resonance occurring within a hollow member in response to the incident waves, and a sound absorbing region is formed, for example, in a frontal direction of the opening portion. Sound scattering effect is achieved through interaction between the above-mentioned interference and interference between the incident waves and sound waves radiated from the opening portion, and a sound scattering region is formed, for example, near the sound absorbing region. A sound scattering effect is achieved by flows of gas molecules being produced in an oblique direction, not normal to the opening portion and reflective surface, due to a phase difference between the sound waves radiated from the opening portion and the sound waves radiated from the reflective surface.

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 includes plate members defining a plurality of hollow regions in parallel relation to each other. Opening portions are formed in one surface (reflective surface) of the plate members in corresponding relation to the hollow regions and in such a manner as to communicate the hollow regions with an external surface. A plurality of sound absorbing members are provided in a dispersed fashion on regions of the one surface (reflective surface) other than the opening portions and neighborhoods of the opening portions. As a modification, a sound absorbing member may be loaded in one of the hollow regions and partly exposed to the outer space through the corresponding opening portion.

Abstract: In a hollow member, a portion of a hollow region adjoining and communicating with an opening portion is constructed as an intermediate layer. The intermediate layer is constructed in such a manner that, when a reflective surface radiates reflected waves corresponding to incident sound waves falling from an external space on the opening portion and the reflective surface of the hollow member, a phase, in the opening portion, of reflected waves produced by resonance of the resonator in response to the incident waves differs from a phase of reflected waves on the reflective surface, and that the absolute value of a value obtained by dividing a specific acoustic impedance of the opening portion by a characteristic impedance of a medium of the opening portion is less than one. A sound absorbing effect through resonance-based action in the opening portion and a sound scattering effect through a flow of gas molecules.

Abstract: Microphone are provided to an intake port of an engine and a wall surface of an engine room on the interior side respectively to collect an engine sound. The engine sound is processed by a signal processing portion and output via a speaker provided to an interior of a vehicle. Filters for simulating the noise insulating characteristic in the interior of the vehicle and filters for processing the engine sound to emphasize the driving conditions are provided to the signal processing portion. Filter characteristics of the filters are decided in response to sensed values of an engine revolution sensor 30, an accelerator opening angle sensor, and a speed sensor. The driving conditions are emphasized by filtering the engine sound based on the filter characteristics.

Abstract: Stereo sound signals are reproduced directly from loudspeakers (SP(L), SP(R)). By using a sum signal and a difference signal of the stereo sound signals as a reference signal, and according to a cross spectrum calculation of the reference signal with a microphone-collected sound signal, calculation is performed to obtain transfer functions of four sound transfer systems between the loudspeakers (SP(L), SP(R)) and microphones (MC(L), MC(R)). The transfer functions obtained are subjected to inverse Fourier transform to obtain impulse responses, which are set in filter means (40-1 to 40-4) to create echo cancel signals and perform echo canceling. This solves the problem of an indefinite coefficient in the echo cancel technique of a multi-channel sound signal.

Abstract: Stereo sound signals are reproduced directly from loudspeakers (SP(L), SP(R)). By using a sum signal and a difference signal of the stereo sound signals as a reference signal, and according to a cross spectrum calculation of the reference signal with a microphone-collected sound signal, calculation is performed to obtain transfer functions of four sound transfer systems between the loudspeakers (SP(L), SP(R)) and microphones (MC(L), MC(R)). The transfer functions obtained are subjected to inverse Fourier transform to obtain impulse responses, which are set in filter means (40-1 to 40-4) to create echo cancel signals and perform echo canceling. This solves the problem of an indefinite coefficient in the echo cancel technique of a multi-channel sound signal.

Abstract: Wall partitioning between outside and inside of a room has an opening portion closed with a film. Sound insulating plate, comprising a lamination of a sound reflecting plate and a sound absorbing member, is supported in opposed relation to the opening portion and at an interval from the opening portion. Sound transmitted from outside of the room into the room through the film is reflected from the sound reflecting plate and then diffracted via sides of the interval, defined between the sound reflecting plate and the wall, to behind the reflecting plate to reach a human listener. Thus, with a mechanical construction, sound, propagated from outside the room into the room, can be made to be heard as sound of frequency characteristics desired by a human listener present in the room.

Abstract: In an acoustic structure, sound absorbing effect is achieved by interference between incident waves falling in an opening portion and reflected waves radiated from the opening as a result of resonance occurring within a hollow member in response to the incident waves, and a sound absorbing region is formed, for example, in a frontal direction of the opening portion. Sound scattering effect is achieved through interaction between the above-mentioned interference and interference between the incident waves and sound waves radiated from the opening portion, and a sound scattering region is formed, for example, near the sound absorbing region. A sound scattering effect is achieved by flows of motion energy of gas molecules being produced in an oblique direction, not normal to the opening portion and reflective surface, due to a phase difference between the sound waves radiated from the opening portion and the sound waves radiated from the reflective surface.

Abstract: In a hollow member, a portion of a hollow region adjoining and communicating with an opening portion is constructed as an intermediate layer. The intermediate layer is constructed in such a manner that, when a reflective surface radiates reflected waves corresponding to incident sound waves falling from an external space on the opening portion and the reflective surface of the hollow member, a phase, in the opening portion, of reflected waves produced by resonance of the resonator in response to the incident waves differs from a phase of reflected waves on the reflective surface, and that the absolute value of a value obtained by dividing a specific acoustic impedance of the opening portion by a characteristic impedance of a medium of the opening portion is less than one. A sound absorbing effect through resonance-based action in the opening portion and a sound scattering effect through a flow of gas molecules.

Abstract: A data converting device includes a first receiving section which receives vehicle driving data of a vehicle from an engine control unit for performing driving control of an engine mounted on the vehicle, and a control section which converts the vehicle driving data into a music performance format, and outputs the converted data.

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: Stereo sound signals are reproduced directly from loudspeakers (SP(L), SP(R)). By using a sum signal and a difference signal of the stereo sound signals as a reference signal, and according to a cross spectrum calculation of the reference signal with a microphone-collected sound signal, calculation is performed to obtain transfer functions of four sound transfer systems between the loudspeakers (SP(L), SP(R)) and microphones (MC(L), MC(R)). The transfer functions obtained are subjected to inverse Fourier transform to obtain impulse responses, which are set in filter means (40-1 to 40-4) to create echo cancel signals and perform echo canceling. This solves the problem of an indefinite coefficient in the echo cancel technique of a multi-channel sound signal.

Abstract: Stereo sound signals are reproduced directly from loudspeakers (SP(L), SP(R)). By using a sum signal and a difference signal of the stereo sound signals as a reference signal, and according to a cross spectrum calculation of the reference signal with a microphone-collected sound signal, calculation is performed to obtain transfer functions of four sound transfer systems between the loudspeakers (SP(L), SP(R)) and microphones (MC(L), MC(R)). The transfer functions obtained are subjected to inverse Fourier transform to obtain impulse responses, which are set in filter means (40-1 to 40-4) to create echo cancel signals and perform echo canceling. This solves the problem of an indefinite coefficient in the echo cancel technique of a multi-channel sound signal.

Abstract: Stereo sound signals are reproduced directly from loudspeakers (SP(L), SP(R)). By using a sum signal and a difference signal of the stereo sound signals as a reference signal, and according to a cross spectrum calculation of the reference signal with a microphone-collected sound signal, calculation is performed to obtain transfer functions of four sound transfer systems between the loudspeakers (SP(L), SP(R)) and microphones (MC(L), MC(R)). The transfer functions obtained are subjected to inverse Fourier transform to obtain impulse responses, which are set in filter means (40-1 to 40-4) to create echo cancel signals and perform echo canceling. This solves the problem of an indefinite coefficient in the echo cancel technique of a multi-channel sound signal.