Abstract: Hydrostatic piezoelectric properties and free-field voltage sensitivity of piezoelectric composites with metal endcap’s “cymbal”was studied. The cymbal design consists of a piezoelectric ceramic disk (PZT-5A) poled in the thickness direction which is sandwiched between two thin metal endcaps, each of which contains a truncated cone-shaped cavity on its inner surface. Piezoelectric composites cymbal was optimized in dimensions and gave effective hydrostatic piezoelectric charge coefficient (d_h^e) values of 6813 pc/N and effective hydrostatic piezoelectric voltage coefficient (g_h^e) values above 580×10^-3 Vm/N which was almost 136 times and 145 times higher than the same size of ceramic element respectively. The free-field voltage sensitivity of -190 dB at 1kHz was obtained.