Abstract: A vibration masking noise system for delivering masking noise into a room or building is designed to vibrate part of the building structure so that masking noise is extended into the room. The system includes a noise generator, a spectrum shaper for shaping the noise, an amplifier for amplifying the shaped noise and a transducer mechanically connected to the structure for converting the masking noise into vibrations of the structure.

Abstract: A dynamic sound controller is designed to automatically adjust and shape the spectral distribution and amplitude of random masking noise before delivery via speakers to the environment of a room according to a preprogrammed timing sequence. In addition, the sound controller is capable of operating as a security and fire alarm system and is further capable of mixing a predetermined amount of background music and paging signals into the same set of speakers. The sound controller of the present invention is further adaptable to a variety of environmental detectors which adjust and shape the noise in response to such factors as temperature, humidity, light level, ionization level and background noise level. A method for shaping spectral distribution and for adjusting amplitude of masking noise in relation to the measured ambient and intrusion noise levels is disclosed.