Main Page | See live article | Alphabetical index A live sound reproduction system has two main forms: A "sound reinforcement" system enhances the volume of the initial sound and will be designed so that as much as possible the listener will not realise that an artificial system is being used to make it easier for them to hear the initial sound. A "PA" (an acronym of "Public Address") is a usually simpler design that just amplifies the initial sound and it will be obvious to the user that it is being used. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.