Precise knowledge of the dependence of elastic modulus and Q factor on the amplitude of excitation is a prerequisite for the development and validation of models to explain the hysteresis observed in quasistatic experiments for various media, i.e., the different deformations at the same applied stress observed when stress change rate is positive or negative. Separation of different contributions to dynamic nonlinearity (e.g., those due to nonequilibrium effects, often termed conditioning) and independent estimation of nonlinearities originated by the strain dependence of velocity and the damping factor are required, which is often not possible with standard approaches. Here we propose and validate a method that, measuring the response of a sample to a monochromatic excitation at different amplitudes, allows fast, continuous, and quasi-real-time monitoring of the dependence of the material elastic properties on amplitude: dynamic elastic modulus (related with velocity through density) and Q factor of the mechanical resonances (related with wave-amplitude attenuation parameters).