Abstract: A bending wave panel-form acoustic radiator formed from sheet material to define an acoustically active area and having at least one integral stiffening member in the form of a corrugation extending out of the plane of the sheet and at least partially across the acoustically active area of the radiator, which stiffening member is of substantially U-shaped cross section. Also disclosed is a method of making a bending wave panel-form acoustic radiator, comprising forming a sheet into a panel having at least one integral corrugation member extending out of the plane of the sheet and at least partly across the sheet and of substantially U-shape cross-section, to stiffen the sheet to have a desired ability to support and propagate bending waves.

Abstract: A vehicle windscreen accessory comprising a body member, an adjustable support structure for the body member whereby the position of the body member can be adjusted, the body member comprising a mirror member and a loudspeaker having a bending wave panel-form acoustic member, the mirror member and panel-form member being integral. The accessory can be in the form of, e.g., a sun visor or a rear view mirror.

Abstract: A bending wave panel-form acoustic radiator formed from sheet material to define an acoustically active area and having at least one integral stiffening member in the form of a corrugation extending out of the plane of the sheet and at least partially across the acoustically active area of the radiator, which stiffening member is of substantially U-shaped cross section. Also disclosed is a method of making a bending wave panel-form acoustic radiator, comprising forming a sheet into a panel having at least one integral corrugation member extending out of the plane of the sheet and at least partly across the sheet and of substantially U-shape cross-section, to stiffen the sheet to have a desired ability to support and propagate bending waves.

Abstract: A method of making a loudspeaker comprising attaching a vibration exciter to a bending-wave panel by bringing the vibration exciter and the panel into contact over an area, and applying ultrasound energy to the contact area.

Abstract: A vehicle windscreen accessory comprising a body member, an adjustable support structure for the body member whereby the position of the body member can be adjusted, the body member comprising a mirror member and a loudspeaker having a bending wave panel-form acoustic member, the mirror member and panel-form member being integral. The accessory can be in the form of, e.g., a sun visor or a rear view mirror.

Abstract: A method of making an acoustical member capable of supporting bending wave vibration. The method comprises the steps of providing a panel (12) to form an acoustic radiator; identifying a position (13) on the panel (12) for mounting a vibration transducer (20) to excite bending waves in the panel; and securing a stiffening member (16) to the panel at the position (13) for mounting the transducer to stiffen the panel locally. Also disclosed is a loudspeaker (10) comprising a bending wave panel-form acoustic radiator (12) and a vibration transducer (20) mounted to the panel (12) to excite bending-wave vibration in the panel, with a stiffening member (16) secured to the panel locally of the transducer.

Abstract: A composite panel (22) comprising a core (24) sandwiched between two faceskins (26), and a method of making the panel. Each faceskin (26) is reinforced with a low weight fibrous veil. The faceskins (26) are bonded to the core (24) using layers of adhesive (28). The composite panel is especially well-adapted for use in a panel-form bending wave loudspeaker.