Abstract: Method and apparatus for determining a position and/or movement of a first part (1) relative to a second part in an electroacoustic transducer to which a signal for conversion is supplied. The method involves the first part (1) being irradiated with beams produced by a radiation source (12, 13), where the radiation source (12, 13) is rigidly connected to the second part, at least some of the beams produced by the radiation source (12, 13) being altered by the first part (1), at least some of the beams altered by the first part (1) being measured using a reception unit (14, 16), and the beams measured in the reception unit (14, 16) being taken as a basis for calculating the position and/or the movement of the first part (1) relative to the second part.