Abstract: A method and apparatus is provided for determining the attenuation coefficients within a body of material by transmitting sonic pressure pulses into the material, analyzing the spectrum amplitude of the echoes returning from the boundaries within the material, calculating the attenuation coefficients of the material between the boundaries and comparing the measured coefficients to those of normal and abnormal tissue. The wave shape of the transmitted pulses is adjusted so that the pulses generate echoes with uniform spectrum amplitude (white echoes) from each boundary within the material. Given the characteristics of the pulses which generate white echoes from the boundaries of each tissue segment and given the thickness of the material between each pair of boundaries, the attenuation coefficients of the material are calculated. The attenuation coefficients are displayed in any manner desired, including traditional B- and M-mode displays.