Abstract:
Ein Lautsprechersystem (1) für ein Kraftfahrzeug weist wenigstens einen Lautsprecher (5) auf, der außerhalb des Passagierraums (3) des Kraftfahrzeugs angeordnet und mittels wenigstens einer Rohrleitung (8) akustisch mit dem Passagierraum (3) verbunden ist. Mit der wenigstens einen von dem wenigstens einen Lautsprecher (5) zu dem Passagierraum (3) führenden Rohrleitung (8) und/oder mit einer anderen, mit dem wenigstens einen Lautsprecher (5) verbundenen Rohrleitung (8) wenigstens ist eine Schalldämpfungseinrichtung (9) verbunden.
Abstract:
An audible alarm has first and second acoustic chambers that deliver sound to respective first and second horns. A phase adjustment circuit for delays the phase of sound generated in one of the two chambers so that sound emerging from the two horns is delivered with the same phase and same frequency, and emerging sound from the two horns is additive.
Abstract:
An earphone for portable electronic apparatus comprising an earphone cable part using a flexible hollow tube uncollapsible in the radial direction having one end facing the speaker of the portable electronic apparatus, and an ear fixing part provided at the other end of the earphone cable part and having an opening communicating with the interior of the earphone cable part, wherein a duct for transmitting a sound generated from the speaker is formed by the earphone cable part and the ear fixing part.
Abstract:
In a method for the transmission of an acoustic signal to a microphone in a photoacoustic cell being part of an apparatus for photoacoustic analysis of substances or gases and in which the zone (40) containing a medium to be analysed represents a damaging environment to the microphone (10), the latter is connected to an excitation zone (30) through a waveguide (20) into which a protecting gas which is chemically neutral to the medium sample has been introduced between the microphone (10) and the medium to prevent the medium from reaching the microphone, the protecting gas being furthermore of a type which allows the waveguide (20) to transmit the acoustic signal generated in the medium through the protecting gas to the microphone without any significant weakening of the signal.
Abstract:
A positionable exhaust apparatus with an exhaust outlet having a first bore extending along a length of the exhaust outlet. The first bore having a longitudinal axis extending the length thereof and an exhaust outlet tip coupled to the exhaust outlet. The exhaust outlet tip having a second bore with at least a portion of the second bore substantially aligned with the first bore of the exhaust outlet. An actuator coupled with the exhaust outlet and the exhaust outlet tip with at least a portion of the exhaust outlet tip to rotate the exhaust outlet tip relative to the exhaust outlet. The exhaust outlet tip rotatable three hundred and sixty degrees about the longitudinal axis of the exhaust outlet.
Abstract:
Underwater voice communication devices and associated methods are described. According to one aspect, an underwater voice communication device includes a voice chamber comprising a face seal which is configured to form at least a substantially watertight seal with respect to a mouth of a first user, wherein the voice chamber comprises an internal volume, an earpiece comprising an ear seal which is configured to form at least a substantially watertight seal with respect to an ear of a second user, wherein the earpiece comprises an internal volume which is in fluid communication with the internal volume of the voice chamber, and wherein the internal volumes of the voice chamber and earpiece communicate voice sound waves from the mouth of the first user to the ear of the second user.