A sound masking system according to the invention is disclosed in which one or more sound masking loudspeaker assemblies are coupled to one or more electronic sound masking signal generators. The loudspeaker assemblies in the system of the invention have a low directivity index and preferably emit an...http://www.google.fr/patents/US7194094?utm_source=gb-gplus-shareBrevet US7194094 - Sound masking system
