A PA system, or public address system, is used to organize large scale audio projection. It is typically used for event spaces, indoors or outdoors, to support loudspeakers and large amplifiers for music or announcements. PA systems can be portable, such as ones used by musicians for instrument amplification or at music festivals. They can also be professionally installed in commercial locations for widespread announcements or alarm systems. The Avico PA loudspeaker is an essential part of a professional PA system. They are most effectively used in packages of 2 or more spread across a large outdoor setting. Any PA system requires an amplifier to provide high quality audio to multiple speakers at once. The Redback Phase5 PA amplifier provides 100 watts of power, suitable for the average professional PA installation.