NOISE-DEPENDENT SOUND VOLUME CONTROL HAVING REDUCED SENSITIVITY TO SPEECH SIGNAL

摘要

The noise-dependent volume control in accordance with the invention is capable of distinguishing between the real background noise and speech in a space (8). The gain (A) of the amplifier (1) is corrected only depending on the level of the background noise, so that once a difference in level between the background noise and a desired signal has been set this is maintained. The volume control is based on repeated measurements of the acoustic signal in the space (8). If it appears that in at least one frequency range the measured energy content (Ei) has fallen at least N times within a range of values DELTA M around a value (Mi) stored in a memory (26) the gain factor is adapted.