Abstract: An auxiliary bass radiator unit is disclosed for mounting in an aperture in a loudspeaker enclosure. The unit comprises a substantially rigid panel member (10) mounted on a flexable surround member (12) so as to allow the panel member, when mounted, in use, in the aperture to move in sympathy with sound waves within the enclosure. The flexable surround member includes a hinge portion (14) mounting the panel member for movement as a hinged flap. Thus, movement of the panel member in twisting and other undesirable modes is substantially avoided.

Abstract: A bandpass loudspeaker enclosure having three sub chambers, a first subchamber being a Helmholtz-reflex chamber with a passive acoustic radiator operating in parallel with the transducer, and the remaining two chambers utilizing two passive acoustic radiators to achieve three Helmholtz-reflex vent tunings and a multiple of low pass acoustic filters that provide an acoustic bandpass with reduced diaphragm displacement and substantially reduced distortion and pipe resonances above the pass band. A further embodiment provides a reduced lowest frequency vent size for a given low frequency subchamber size and tuning frequency.

Abstract: In a preferred embodiment, a bandpass loudspeaker enclosure includes three sub chambers, a first one being a non-Helmholtz-reflex chamber of a sealed acoustic suspension construction, and the remaining two chambers utilizing two passive acoustic radiators to achieve two Helmholtz-reflex vent tunings and a multiple of low pass acoustic filters that provide an acoustic bandpass with a substantially 2nd order high pass characteristic combined with an extended, steeper, at least 4th order slope low pass stop band characteristic.

Abstract: A moving-armature transducer assembly suitable for use as an alerter in a portable telephone. The assembly includes a transducer housed in an enclosure including first and second acoustical chambers. A first sound emitted from a front hole on a front side of the transducer is propagated through the first acoustical chamber and emitted from a first port of the assembly. A second sound emitted from a rear hole on a rear side of the transducer is phase-shifted by the second acoustical chamber acting in combination with a second port or ports on the assembly to have a phase coinciding with the phase of the first sound. The second sound then combines with the first sound, reinforcing the first sound and producing a combined sound having an increased level and bandwidth.

Abstract: A broadband loudspeaker radiating as an approximate point source, whose movable components are fastened to a dome-shaped loudspeaker front, wherein the loudspeaker front flares rearwardly to an enclosure shell disposed coaxially around the central axis of the enclosure and a diagonally disposed deflection plane, which can be formed as the back wall, faces the back side of the diaphragm. The inside cross section of the enclosure shell is preferably a polygon with an odd number of sides, as is the dome-shaped loudspeaker front and the loudspeaker diaphragm, which is preferably cup-shaped and which can be fastened directly to the loudspeaker front.

Abstract: A loudspeaker system includes an acoustical enclosure having an internal wall for dividing the enclosure into first and second sub-chambers. An electro-acoustical transducer having a vibratable speaker cone is mounted in an opening provided in the internal wall of the acoustical enclosure, while an internal vent is provided in the internal wall of the acoustical enclosure for pneumatically coupling the first and second sub-chambers. An external vent is provided in a wall of the first sub-chamber for pneumatically coupling the first sub-chamber to an exterior environment outside of the acoustical enclosure. Finally, a passive radiator is provided in a wall of the second sub-chamber for pneumatically coupling the second sub-chamber to the exterior environment.

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: A diaphragm-type bass loudspeaker has a housing (10), the housing walls (13, 14, 15) of which enclose a volume (25) which is formed on the rear side of its diaphragm (3). In a surface area of the housing walls (13, 14, 15) which bounds the volume (25) there is an opening (23).

Abstract: The present invention is an improved loudspeaker enclosure port with internal longitudinal dividers which help reduce turbulence in the port and control port selfresonance. Preferred embodiments of the present invention comprise a central circular tube or rod with radial dividers connecting the central tube to the internal wall of the port. The internal longitudinal dividers of the present invention are thought to reduce air friction losses in the port and to reduce cross-flow turbulence in the port yielding a more responsive speaker with more uniform aerodynamic drag on the driver diaphragm.

Abstract: A speaker apparatus comprises a speaker unit, a cabinet for forming an internal space on the rear side of the speaker unit with a plurality of wall surfaces including a baffle plate for use in mounting the speaker unit, a acoustic tube which is formed along at least one wall surface out of the plurality of wall surfaces and has not only a substantially uniform hollow section but also an opening at one end, and an acoustical material for separating the internal space from the internal space of the acoustic tube by closing the opening of the acoustic tube. The speaker apparatus is characterized in that the acoustic tube has a tube length about 1/(2n) (n=positive integer) time as large as a wavelength corresponding to the lowest resonance mode of the standing wave produced along the one wall surface out of the standing waves produced in the internal space and that the opening is disposed close to the node of the standing wave.

Abstract: A speaker apparatus comprises an enclosure including a front panel and having a sealed compartment and a ported compartment. A first driver is mounted in the front panel and within the sealed compartment. An internal passive radiator is mounted in the enclosure. A radial port is formed in the enclosure front panel and is disposed at a position facing the internal passive radiator. The speaker apparatus also includes a second driver mounted in the front panel and within the sealed compartment. The internal passive radiator is mounted between the first and the second drivers.

Abstract: A driver unit is fixed to a stand. A front box and a rear box are directly fitted to the stand through a buffer material. A box comes into contact with the driver unit through a buffer material and is fixed to the stand. Therefore, sound of the driver unit is not transmitted to the box and the drop of sound quality of the speaker can be prevented. The driver unit is fixed to the stand at an immovable foundation, and sound energy can be efficiently transmitted from a speaker cone to the air.

Abstract: A loudspeaker system comprises an enclosure which accommodates a loudspeaker device and a bass-reflex port (105). The port has two open ends (105b, 105c) and a central area (c) provided with perforations (109), as well as a foam material (111) provided in and/or on the perforations.

Abstract: An electro-acoustic transducer, such as a speaker device or an earphone device. The transducer includes an electro-acoustic transducing unit, such as a speaker unit, for converting input electrical signals into the 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 on being transmitted into the inside of the sound duct to prevent the radiated sound from being re-admitted into the electro-acoustic transducer.

Abstract: A moving-armature transducer assembly suitable for use as an alerter in a portable telephone. The assembly includes a transducer housed in an enclosure including first and second acoustical chambers. A first sound emitted from a front hole on a front side of the transducer is propagated through the first acoustical chamber and emitted from a first port of the assembly. A second sound emitted from a rear hole on a rear side of the transducer is phase-shifted by the second acoustical chamber acting in combination with a second port or ports on the assembly to have a phase coinciding with the phase of the first sound. The second sound then combines with the first sound, reinforcing the first sound and producing a combined sound having an increased level and bandwidth.

Abstract: A speaker system includes a speaker box and a speaker mounted thereon. A bass reflex duct is provided in the speaker box at a position corresponding to an approximate center portion of the speaker. In addition, another duct is provided around the speaker in the speaker box. The bass reflex duct is arranged inside of a duct so that the bass reflex duct and the duct overlap each other. The speaker system is arranged to efficiently direct the back pressure of a speaker to the bass reflex duct and greatly increases the sound pressure in resonance even when a compact speaker box is used.

Abstract: According to the invention, a bass reproduction device is disclosed, with which the sound emission from the membrane (15) to the listening space (38) is carried out solely by way of a displacement volume (37) and at least one sound guidance conduit (34), whose cross section is smaller than the cross section of the membrane (15). A device of this kind has the advantage that for sound emission, only wall surfaces have to be supplied, which merely have to contain the sound guidance conduit(s) (34). The side of the membrane (15) remote from the displacement volume (37) acts on a closed damping volume (30), which can, however, be changed in its size over a great band width. A particularly favorable bass reproduction is achieved if the length of the respective sound guidance conduit (34)≦&lgr;/8 of the desired upper cross-over frequency.

Abstract: The latest advances in speaker driver design have resulted in high output drivers with superior low frequency response, power handling, and linear excursion than conventional drivers. These new drivers present further problems to enclosure design due to large port surface area and long port length requirements. The present invention wraps a port completely around an enclosure, maximizing port surface area and placing the consequently lengthy port in a more practical position. The port of the present invention converts a circular cross-section to an annular cross-section with constant cross-sectional surface area, thus integrating a large port into an enclosure without a large dimensional increase. In one embodiment, a bandpass configuration demonstrated a reduction in port air displacement and noise. Response deviations in the present invention due to flaws in construction and open pipe resonance can be alleviated through the use of plastics and filters, respectively.

Abstract: A speaker system having increased sound quality comprising a first and second speakers each having a front and back. The first and second speakers cooperate with a duct having a first elongated portion in fluid communication with the rear of the first speaker and a second elongated portion in fluid communication with the rear of the second speaker. The duct has an elongated bass port defined therein intermediate the first and second portions. Each of the speakers have their fronts in contact with the air outside of the duct and the backs of the speakers are in contact with the air inside the duct. The duct may have a first spur intermediate the first and second speakers with a bass port in the first spur. The duct may have a second and third spur at the axial extremities with the first and second speakers respectively engaging the second and third spurs. Each spur may have an axis and the axes of the spurs may be generally coplanar for automobile use.

Abstract: A speaker system excellent in reproduction in bass range, which comprises a reinforcing post 3a to abut against the back side of a speaker unit 5 installed in a front cabinet 2. The reinforcing post 3a is formed integrally in a back cabinet 3, and is fixed with a cover 4. In this constitution, unwanted vibrations generated in the back cabinet 3, cover 4, and speaker unit 5 due to rear release wave b can be suppressed.

Abstract: A bass reflex-type loudspeaker having enhanced low frequency response and enhanced power handling capacity comprises a low frequency loudspeaker mounted in a ported enclosure whose walls are made purposefully resonant, the front baffle and rear surface of the enclosure connected by a sound post which serves to acoustically couple the front and rear enclosure surfaces.

Abstract: A loudspeaker system having a multiple driver array arranged in a push-pull configuration is loaded into an acoustic transmission line ported to the outside of the loudspeaker enclosure. The transmission line is preferably tapered and is filled with acoustic damping material. The combination of the push-pull driver configuration loaded into an acoustic transmission line produces a high performance, spatially enhanced sound reproduction.