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.