This paper investigates a nonreciprocal sound transmission effect provided by a triangular lattice two-dimensional sonic crystal made of rods in a triangular cross-section. This sonic crystal (SC) device works as a frequency selective acoustic diode operating at a frequency of 8950 Hz. The scatterer matrix of the sonic crystal diode prototype was composed of triangular shaped wood rods that break the symmetry of the spatial inversion and provide nonreciprocal wave transmission with a contrast rate of 89% in experiments. This acoustic diode device can provide a high contrast, narrow band, one-way sound transmission for acoustic wave control applications. (c) 2013 Elsevier Ltd. All rights reserved.