A keyboard device and a musical sound emission method are provided. A top lid is formed into a hollow structure including a lower plate and an upper plate facing the lower plate. Since vibrating bodies are fixed to an inner surface of the lower plate, the vibrating bodies can cause the lower plate to vibrate and thereby emit musical sound generated through the vibration from an outer surface side of the lower plate to the outside. On the other hand, the musical sound emitted from an inner surface side of the lower plate is blocked by the upper plate, and it is thus possible to curb mutual cancelation of musical sound in opposite phases emitted from each of the inner surface and the outer surface of the lower plate. Therefore, it is possible to efficiently emit musical sound to the surroundings of the top lid.

A flow controlled sound generation system is disclosed that includes one or more fluid pumps to control air flow through a sound channel. The air flow is modulated through one or more valves to produce audible frequency pressure waves.

A flow controlled sound generation system is disclosed that includes one or more fluid pumps to control air flow through a sound channel. The air flow is modulated through one or more valves to produce audible frequency pressure waves.

Exposure to sunlight is minimized.

A vibration generation device 1 includes a vibration generator that generates a vibration, and a vibration transmission member 4 that has a vehicle-side fixed part 30 to be fixed to a vehicle 50 and transmits to the vehicle 50 the vibration generated by the vibration generator, wherein the vehicle-side fixed part 30 is provided within a range R of the vibration generator, as viewed from the vibration direction of the vibration generator.

Aspects of the disclosure relate to using a display as a sound emitter and may relate to an electronic device including a display and for sound leak cancellation. A vibration sensor such as an accelerometer is physically coupled to the display and senses the display vibration to provide a signal representing actual acoustic output from the display. The electronic device includes a first actuator physically coupled to the display and configured to cause vibration of the display in response to a first audio signal. The electronic device further includes the vibration sensor configured to output a vibration sensor signal proportional to the vibration of the display. The electronic device further includes a second actuator physically coupled to a portion of the electronic device different from where the first actuator is physically coupled to the display and configured to cause vibration of the portion in response to a second audio signal.

An electronic horn includes a cover (8) on a front side of an intermediate element (6). A first passage (P1) within the horn is defined by a central portion (82) of the cover (8) that projects into a cylindrical interior of a cylindrical water-proofing wall (621). Second passages (P2, P3, P4) extend generally concentrically with respect to the first passage (P1) and are respectively defined by water-proofing walls (83, 84) that are formed on the cover (8) and project into the interior spaces of water-proofing walls (622, 633). The outermost second passage (P4) opens toward the forward direction. The first and second passages (P1-P4) extend in a back-and-forth path that prevents any rainwater, which has entered the interior of the horn through the opening of the outermost second passage (P4), from reaching a resonance space (7) defined between the resonator (7) and a sound-generating oscillator (51).

A sound producing device includes a first sound producing cell, driven by a first driving signal and configured to produce a first acoustic sound on a first audio band, and a second sound producing cell, driven by a second driving signal and configured to produce a second acoustic sound on a second audio band different from the first audio band. A first membrane of the first sound producing cell and a second membrane of the second sound producing cell are Micro Electro Mechanical System fabricated membranes. The first audio band is upper bounded by a first maximum frequency; the second audio band is upper bounded by a second maximum frequency. A first resonance frequency of the first membrane is higher than the first maximum frequency of the first driving signal. A second resonance frequency of the second membrane is higher than the second maximum frequency of the second driving signal.

An ultrasonic transducer for wind turbine applications. The transducer includes a housing with a central diaphragm portion, a peripheral wall thereabout, and a flexure portion supporting the diaphragm portion relative to the peripheral wall. The apex of a cone is secured to the housing central diaphragm portion and the cone has a peripheral rim secured to the metal housing peripheral wall. A driver such as a piezoelectric element is secured to the housing central diaphragm portion opposite the cone apex.

A notification appliance is disclosed and includes a sound engine that generates sound according to an acoustic pattern and the power control that regulates input voltage to the sound engine that is matched to the acoustic pattern. A method of powering a sounder is also disclosed and includes providing a constant input current and regulating an input voltage to a phase of a sound engine corresponding with an acoustic signal generated by a sound engine.

A notification appliance is disclosed and includes a sound engine that generates sound according to an acoustic pattern and the power control that regulates input voltage to the sound engine that is matched to the acoustic pattern. A method of powering a sounder is also disclosed and includes providing a constant input current and regulating an input voltage to a phase of a sound engine corresponding with an acoustic signal generated by a sound engine.