Also known as “PA” or P.A.” Short for “public address” or “public address system,” this is a term that refers to a sound system used for amplifying announcements, speech, or pre-recorded music playback throughout a venue such as an auditorium, school, church, retail store, or other site. Though the term is popularly used synonymously with “sound system” or “sound reinforcement system,” many audio engineers prefer to distinguish between the type of multi-speaker system used for announcements in a school (for example) versus a system specifically designed for reinforcing live music performances in concert situations.