Abstract: For the automatic evaluation of the transmission quality of a voice signal that is transmitted by a digital transmission system (1) frequency components that correspond to a data frame rate (fr) of the digital transmission system (1) are extracted from the received voice signal and analyzed. In order to obtain a measurement value that is independent of signal strength, a standardization with the spectral output values occurring in the middle of the quoted frequencies can be conducted. For comparison purposes, an undistorted voice signal is processed the same way in advance. The measurement values of the transmitted voice signal are placed at a ratio to the reference values and then evaluated, e.g., by a neuronal network (13).