An audio system is one of the basic components of a humanoid robot designed for natural interaction. For many interaction purposes it is sufficient to use the sound detection and localization as attention system for the vision system. In this paper the audio perception module of the robot ROMAN is presented including the integration into the existing control structure and the localization algorithm using a microphone array with 6 microphones. The reduction of data into so called sector maps is presented and the interaction with the control architecture is shown.