Abstract: A method and apparatus for masking sound is disclosed. A master sound masking unit (14) having a sound masking generator (20), an amplifier (22), a ten-octave equalizer (24) and a dual voice coil speaker (26) therewithin. Slave sound masking units (16) are connected to master unit (14) by detachable cables (18). Master unit (14) may also be used alone without slave units (16). If used with slave unit (16), master and slave units are arranged into zones and connected and adjusted in accordance with the method for producing optimum sound masking results described herewithin.