The public address systems are used to provide the security in crowded areas such as supermarkets, malls and big offices. The broadcasting systems usually provide the music playback in the premises, transmit advertising and official messages. In case of an emergency the music broadcasting stops and triggers the alarm, which may sound like a siren or voice message to evacuate. The voice messages for alarm systems the most often are written in advance. The majority of the voice alarm systems allow one to record using a built-in microphone or a dictophone, the length of messages is usually about 2 minutes. The playback of the messages to evacuate can be programmed to broadcast one after another in different areas, which is necessary to prevent the panic. The public address system is a radio-electronic unit that connects to the acoustic system of the building. The fire alarm system or any other system that provides the security of the building transmits radio-electronic signal to the unit, which in turn puts the system into alert mode.