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 system includes a speaker cabinet that has an opening, a first speaker including a first diaphragm, and at least one acoustic tube opened at both ends. When an amplitude of vibration of the first diaphragm vibrated by applying a correction AC signal together with the first AC signal to the first speaker is equalized to the amplitude of vibration of the second diaphragm, a sound pressure reproduced by vibration of the first diaphragm is equal to or lower than a sound pressure reproduced by vibration of the second diaphragm of the second speaker. This is accomplished by applying a third AC signal having a frequency equal to or higher than a minimum resonance frequency of the closed type cabinet determined by the internal volume of the closed type cabinet and the caliber of the second speaker is applied to the second speaker.

Abstract: A speaker system with an enclosure having a spiral pathway is presented. The speaker system includes an electro-acoustic transducer that generates sounds according to an audio input. The speaker system also includes an enclosure having an interior pathway defined by a wall that is curved substantially as a spiral. The speaker system is configured such that the sound generated by the electro-acoustic transducer travels along at least a portion of the curved pathway before leaving the enclosure.

Abstract: A behind the detector sounder has a base plate and walls which define mechanical horns having throats which open into a space at the centre of the base plate. The mouths of the mechanical horns are at the outer periphery of the base plate and the walls bound sound paths which are longer than the straight line distance from the throat of each mechanical horn to the mouth of that mechanical horn.

Abstract: A horn guard device for a motorcycle having an aesthetic appearance improved and being capable of meeting legally-specified values for a horn sound pressure in different countries. A spiral-type horn is attached onto a down tube with its sound-pressure outlet facing the road surface. The horn is placed downward of an engine. A water-exposure guard is provided facing a front portion of the sound-pressure outlet. The water-exposure guard faces the sound-pressure outlet with a predetermined angle therebetween. The water-exposure guard can be integrally formed on a lower portion of a bracket attached to bosses extending to the side from the down tube.

Abstract: A loudspeaker enclosure has a first aperture in which a driver can be mounted, the driver having a first resonant frequency. A second aperture defines a port extending between the interior and the exterior of the enclosure. The port is tuned to a second resonant frequency. A sound absorbing element comprises at least one exponentially tapered horn having a mouth in communication with the interior of the enclosure. The horn has a cut-off frequency equal to or greater than the resonant frequency of the port, and preferably two to four times greater. The horn can be defined by tapering external walls of the enclosure, or by structures located within the enclosure which define a plurality of individual horns. The described enclosure combines the benefits of ported enclosures with those of enclosures employing tapered sound absorbing elements.

Abstract: A method and a loudspeaker construction (10), in which loudspeaker construction spherical acoustic wave fronts emitted by the diaphragms (12) of speaker elements (11) are transformed into a uniform, planar acoustic wave front. The loudspeaker construction (10) comprises a plane wave channel (20), in the surface (26) of which plane wave channel directed towards the diaphragm (12) there are adjacent sound inlet apertures (24) for transmitting acoustic waves into ducts (23) and, on the opposite side (22) of the plane wave channel, there are outlet apertures (25) for transmitting acoustic waves from the ducts into a horn portion (30). The ducts (23) taper so that the width (B) of the outlet apertures located in a row on the side of the horn portion is less than half the diameter (D) of the diaphragm.

Abstract: A horn assembly for a motor vehicle includes a sound generating member, a housing having a first opening connected to the sound generating member and a second opening to disperse sound from the sound generating member, and a deflector to restrict ingress of liquid into the second opening, while allowing egress of sound from the second opening. The deflector includes a base member having a first end coupled to the housing and a second end defining a portion of a primary opening to direct dispersement of sound from the sound generating member. The deflector includes a first lateral wall and a second lateral wall, where each lateral wall is coupled to the base member and extends toward the housing. A distal edge of each of the first and second lateral walls is spaced apart from the housing to form secondary openings allowing dispersement of sound from the housing.

Abstract: A speaker enclosure including a compact quarter wavelength transmission path in the shape of a closed spiral that expands radially outward from a centrally located loudspeaker mounting location. The height of the transmission path has a minimum height that is equal to the height of the basket of the desired speaker. The quarter wavelength transmission path spiral of the provides an aerodynamic path for air flow therein which reduces the turbulence of air flow to a minimum that in turn provides even resistance to the air flow within the transmission line (Exhale vs. Inhale).

Abstract: An apparatus for increasing the quality of sound from an acoustic source comprises in one embodiment a hollow enclosure, an acoustic source, an acoustic guide, a pair of acoustic inlet openings, a pair of acoustic exit openings, and pair of acoustic paths, wherein the acoustic inlet openings separate acoustic waves from the acoustic source and direct the acoustic waves the length of the acoustic paths to the acoustic exit openings in such a manner as to increase the quality of sound, and especially bass sound, from the acoustic source.

Abstract: The invention features an acoustic waveguide and system for transmitting pressure wave energy produced by an electroacoustical transducer in a medium that propagates pressure wave energy. The acoustic waveguide and system includes a tube defining a spiral-shaped channel with a length of L. The tube has a first end and a second end with the first end closed and the second end open to the medium. The tube has a transducer opening for accommodating an electroacoustical transducer located between the first and second end of the tube. The system includes an electroacoustical transducer mounted to the acoustic waveguide.

Abstract: The invention features an acoustic waveguide and system for transmitting pressure wave energy produced by an electroacoustical transducer in a medium that propagates pressure wave energy. The acoustic waveguide and system includes a tube defining a spiral-shaped channel with a length of L. The tube has a first end and a second end with the first end closed and the second end open to the medium. The tube has a transducer opening for accommodating an electroacoustical transducer located between the first and second end of the tube. The system includes an electroacoustical transducer mounted to the acoustic waveguide.

Abstract: An electro-acoustic transducer, such as a speaker device or an earphone device. Includes an electro-acoustic transducing unit, such as a speaker unit, for converting input electrical signals into sound, a casing in which the electro-acoustic transducing unit is arranged and which delimits a back cavity towards the rear side of the electro-acoustic transducing unit, and at least two openings having a sound duct communicating with the back cavity. The sound radiated from the back surface of the electro-acoustic transducing unit is attenuated by being transmitted into the inside of the sound duct to prevent the radiated sound from being re-admitted into the electro-acoustic transducer.

Abstract: An electronic horn of compact dimensions. Oscillator circuits coupled to a mixing node produce a multiple frequency signal used to drive a horn transducer. One horn replaces the two horns used in the prior art. A reverberating chamber in close proximity to the transducer includes a cone shaped structure having multiple spiraling reflecting walls connected to the convex surface of the cone. Sound waves emitted by the transducer reverberate within the chamber as they bounce off the reflecting walls.

Abstract: An electrically driven loudspeaker is coupled to the atmosphere, which is to carry sound to the human ear, through a hollow coupler the inlet end of which has a cross sectional area comparable to the effective area of the loudspeaker, said cross sectional area decreasing progressively from said inlet end to an outlet end of substantially smaller cross sectional area. In a specific embodiment of the invention, an exponential horn is formed within the confines of a loudspeaker cabinet enclosure, and the inlet end of the horn is coupled to the electrically driven loudspeaker by means of the hollow coupler also formed within the cabinet enclosure. The outlet end of the coupler has the same cross sectional area and shape as the inlet end of the horn.