Abstract: An acoustic apparatus includes a vibration part configured to generate an acoustic vibration, a tube having a cavity that faces the vibration part, and at least one open tube connected to the tube via a first open end and a second open end. A length of the at least one open tube is an integer-fold of substantially a half of a wavelength of a standing wave produced in the tube. The first open end is positioned substantially at an anti-node of the standing wave produced in the tube.

Abstract: A microphone device includes: a housing having an opening section in an upper face thereof; and a non-directional microphone unit incorporated in the housing and provided inside the opening section. The upper face of the housing has a shape in which a distance from an edge defined as a boundary between the upper face and a side face or a bottom face to the opening section throughout a whole circumference of the upper face changes in ½ or more of the whole circumference of the edge and an average value of the distance from the edge to the opening section is shorter than ½ of a wavelength of a sound wave in a frequency range in which an auditory sensitivity of humans is low.

Abstract: An audio device is provided with a plurality of Helmholtz resonators. Whereas a cross-sectional area of a neck and a volume of a cavity communicating with the neck are same between at least two of the Helmholtz resonators, a ratio of minimum and maximum values of distances between a center of gravity of the cross section of the neck and individual points defining an outer periphery of the cross section is different between said at least two of the Helmholtz resonators.

Abstract: A microphone device includes: a housing having an opening section in an upper face thereof; and a non-directional microphone unit incorporated in the housing and provided inside the opening section. The upper face of the housing has a shape in which a distance from an edge defined as a boundary between the upper face and a side face or a bottom face to the opening section throughout a whole circumference of the upper face changes in ½ or more of the whole circumference of the edge and an average value of the distance from the edge to the opening section is shorter than ½ of a wavelength of a sound wave in a frequency range in which an auditory sensitivity of humans is low.

Abstract: A speaker includes: one or more speaker units; a cabinet accommodating the one or more speaker units; and a speaker net mounted on one of the cabinet and at least one of the one or more speaker units so as to cover a sound emitting surface of each of the at least one of the one or more speaker units. The speaker net includes: a frame surrounding the sound emitting surface of each of the at least one of the one or more speaker units; and a sheet member stuck to the frame to cover the sound emitting surface of each of the at least one of the one or more speaker units. The frame being formed with at least one through hole establishing communication between (i) a space between the frame and the cabinet and (ii) a space outside the speaker.

Abstract: An acoustic apparatus includes a vibration part configured to generate an acoustic vibration, a tube having a cavity that faces the vibration part, and at least one open tube connected to the tube via a first open end and a second open end. A length of the at least one open tube is an integer-fold of substantially a half of a wavelength of a standing wave produced in the tube. The first open end is positioned substantially at an anti-node of the standing wave produced in the tube.

Abstract: A speaker, including: a casing having a baffle plate; and a sound source fixed to the baffle plate of the casing, wherein at least one cutout is formed in the baffle plate, the at least one cutout having a configuration in which a width of the at least one cutout increases with an increase in a distance from the sound source.

Abstract: In a bass reflex type speaker, a Helmholtz resonator is formed by a bass reflex port and a space within a speaker enclosure excluding the bass reflex port and a speaker unit. The bass reflex port of the bass reflex type speaker is movable toward and away from a side surface while maintaining its projecting direction within the speaker enclosure. In response to such movement of the bass reflex port, relative positional relationship between a neck and cavity of the bass reflex type speaker varies.

Abstract: An audio apparatus includes a housing including a space which is enclosed at least one pair of opposite surfaces, and an open pipe including a first open end and a second open end positioned in the space. The open pipe has a pipe length of integral multiple of a substantially half wavelength of a stationary wave which is generated in the space. The first open end of the open pipe is disposed at a position of a substantial loop of the stationary wave which is generated in the space.

Abstract: An audio apparatus includes a housing including a space which is enclosed at least one pair of opposite surfaces, and an open pipe including a first open end and a second open end positioned in the space. The open pipe has a pipe length of integral multiple of a substantially half wavelength of a stationary wave which is generated in the space. The first open end of the open pipe is disposed at a position of a substantial loop of the stationary wave which is generated in the space.

Abstract: An audio device is provided with a plurality of Helmholtz resonators. Whereas a cross-sectional area of a neck and a volume of a cavity communicating with the neck are same between at least two of the Helmholtz resonators, a ratio of minimum and maximum values of distances between a center of gravity of the cross section of the neck and individual points defining an outer periphery of the cross section is different between said at least two of the Helmholtz resonators.

Abstract: In a bass reflex type speaker, a Helmholtz resonator is formed by a bass reflex port and a space within a speaker enclosure excluding the bass reflex port and a speaker unit. The bass reflex port of the bass reflex type speaker is movable toward and away from a side surface while maintaining its projecting direction within the speaker enclosure. In response to such movement of the bass reflex port, relative positional relationship between a neck and cavity of the bass reflex type speaker varies.