GTM-Grup de recerca en Tecnologies Mèdia, La Salle, Universitat Ramon Llull, C/Quatre Camins 2, 08022 Barcelona, Catalonia, Spain.
J Acoust Soc Am. 2013 Aug;134(2):EL153-7. doi: 10.1121/1.4812446.
This manuscript presents some recent results on directivity control and efficiency of parametric loudspeakers utilizing horns. Horns act both like an acoustic transformer and a directivity control method. An experimental device has been built and measurements have revealed that the horn has a clear influence on the audible sound levels and directivity of the parametric loudspeakers. When compared with a conventional megaphone, a much more flat frequency response is obtained and the resulting directivity is shown to be almost frequency independent.
本文介绍了一些关于利用号角控制参量扬声器指向性和效率的最新研究成果。号角既可以作为声学变压器，也可以作为指向性控制方法。已经建立了一个实验装置，并且测量结果表明，号角对参量扬声器的可听声级和指向性有明显的影响。与传统的扬声器相比，获得了更加平坦的频率响应，并且显示出的指向性几乎与频率无关。
