| 20100249635 | HEARING SCREENING SYSTEM FOR A SUBJECT OR A PATIENT, AND A METHOD FOR HEARING SCREENING - An auditory stimulus device in a first aspect for applying an auditory stimulus to at least one ear of a subject; at least three electrodes for electrically connecting to at least three different positions on a head of the subject for measuring respective potential changes in response to the auditory stimulus; two galvanically isolated power supplies; two differential amplifiers arranged for receiving galvanically isolated supply voltages from the power supplies. In a second aspect the system comprises one (or more) electroencephalographic (EEG) channels with one differential amplifier, wherein the differential amplifier is arranged for amplifying a potential difference between the pair of electrodes for obtaining an amplified EEG signal on an output of the differential amplifier, wherein the differential amplifier is configured for first amplifying the potential difference with a total differential gain and subsequently taking a difference between respective output potentials of the amplified potential difference. | 09-30-2010 |