Abstract: In system for recording and processing a signal for diagnosing an auditory system, a system for measuring signals of bioelectric activity of brain (EEG signal) or eye (EOG signal) or muscle (EMG signal) or their combination obtained from electrodes (11, 21, 22) attached to head skin of a person to be tested communicates with system (105) informing about sleep phase occurrence through an input (27). A system for measuring an auditory brainstem response signal (ABR signal) evoked by acoustic stimulation is automatically activated by a circuit (106) for automatic activation connected to the system (105) informing about sleep phase occurrence and measures the ABR signal. The system also includes a recording system (101, 102) of the ABR signal in a configurable period of time measured from the time of acoustic stimulation and system (103) to present the ABR signal in graphical form.