| 摘要 |
<p>An elongate acoustic radiator consisting of an exciter (11), that propagates mechanical waves directly or by an adapter (12) to a mechanical waveguide. Therefore mechanical waves travel along the waveguide axed with wave velocity cw. The waves cause local displacement of transformer elements (14) coupled to the waveguide that are transformed into acoustical radiation. The waveguide is terminated with an impedance termination. Local sound radiations interfere and direct inphase radiation follows. The input impedance, the directivity characteristic, the areas of the same phase and the efficiency of the radiation can be adjusted by the points of excitation, the wave velocity, the length of the waveguide, the amplitudes of displacement, the properties of the transformer and the impedance termination. The volume of the enclosure is adjusted by the properties of the waveguide and the transformer. The device can be used as a signaling device, for speech, music or as a microphone.</p> |
