Abstract: The present invention relates to a loudspeaker array comprising: a high frequency driver and a midrange driver forming a unitary assembly and configured to direct acoustic waves towards a listener in front of the loudspeaker array along an axis in a forward direction; at least one low frequency driver located generally rearwardly of the unitary assembly, and a woofer volume extending along and perpendicular to the axis between the at least one low frequency driver and the unitary assembly, in which the rear of the unitary assembly is configured and acoustically open so as to allow sound from the rear of the midrange driver to radiate rearwardly into the woofer volume.

Abstract: Electrical circuitry adapted to drive a dual-coil loudspeaker having a primary voice coil and a second voice coil connected in parallel with the primary voice coil, the second voice coil being in series with an LC resonant circuit of impedance Zmf, further comprising an inductance compensation filter of impedance Zif in parallel with the LC resonant circuit.

Abstract: A loudspeaker comprising: an acoustic diaphragm having front and rear surfaces, the acoustic diaphragm in use being driven so as to vibrate and radiate acoustic waves from its front surface in a forward direction away from the loudspeaker and from its rear surface in a rearward direction, and a drive unit located rearwardly or to the front/outside of the diaphragm, there being at least one open duct leading in a rearward direction away from the diaphragm, in which the at least one open duct has a cross-sectional area which decreases in the rearward direction, and in which acoustic waves radiated from the rear surface of the diaphragm pass through the open duct before contacting a front surface of an acoustic metamaterial absorber located generally behind the drive unit and immediately to the rear of the duct.

Abstract: The present invention relates to a loudspeaker array comprising: a high frequency driver and a midrange driver forming a unitary assembly and configured to direct acoustic waves towards a listener in front of the loudspeaker array along an axis in a forward direction; at least one low frequency driver located generally rearwardly of the unitary assembly, and a woofer volume extending along and perpendicular to the axis between the at least one low frequency driver and the unitary assembly, in which the rear of the unitary assembly is configured and acoustically open so as to allow sound from the rear of the midrange driver to radiate rearwardly into the woofer volume.

Abstract: A loudspeaker comprising: an acoustic diaphragm having front and rear surfaces, the acoustic diaphragm in use being driven so as to vibrate and radiate acoustic waves from its front surface in a forward direction away from the loudspeaker and from its rear surface in a rearward direction, and a drive unit located rearwardly or to the front/outside of the diaphragm, there being at least one open duct leading in a rearward direction away from the diaphragm, in which the at least one open duct has a cross-sectional area which decreases in the rearward direction, and in which acoustic waves radiated from the rear surface of the diaphragm pass through the open duct before contacting a front surface of an acoustic metamaterial absorber located generally behind the drive unit and immediately to the rear of the duct.