WO15044000A1 [EN] The invention relates to a device (10) comprising a useful signal detector (12) and a sound reproducer (14). Said useful signal detector (12) is designed to extract a useful signal (20a) from a sound signal (16) in the surroundings (18) of the device (10) and to separate from an interfering signal (22) in the sound signal (16). Said sound reproducer (14) is designed to reproduce the useful signal (20b) in an aligned manner and to superimpose on the sound signal (16).