A thermochemical code, SIAME, dedicated to the study of high explosives, is currently being validated. From this code, both the parameters of the JWL equation of state of a given composition are calibrated from the calculated adiabatic curve and tabulated equations of state are constructed. SIAME code uses BKW equations with a specific calibration presented in this study. Calculated adiabatic curves are compared with the one obtained with the American code CHEETAH with the BKWC, BKWS and EXP6 calibrations for two different high explosive formulations: a melt-cast one (RDX/TNT 60/40 % wt.) and a pressed one (HMX/Viton 96/4 % wt.). The validity of the constant entropy curves obtained with the JWL EOS and the tabulated EOS is investigated from the Chapman-Jouguet state to several dozens of megapascals to cover all the high explosive effects. Experimental results obtained for the two high explosives with the cylinder test and the impedance matching test are presented in this study and offer a set of validation points.