In the paper we present the results of measurements of sound speed in zinc single crystals with orientation ⟨0001⟩ at initial temperatures 17°C and 322°C over the stress range from 13 GPa of shock compression down to −2 GPa of tension. Within this stress range zinc of given orientation is elastic. The method is based on the measurement and analysis of wave reverberation in a plate, one surface of which is free whereas other surface contacts with a high‐impedance material (molybdenum). The results were confirmed by computer simulation. Nonlinearity of longitudinal compressibility of zinc exceeds that of the bulk compressibility. © 2004 American Institute of Physics