public address system
P.A. system
PA system
P.A.
PA

The P.A. system blared into life; the horses were on the track for the first race.

As for hearing music outside, the signal coming out of a big P.A. system faces many obstacles.

The P.A. system in the ceiling spoke more clearly.

There came the sudden voice of the P.A. system.

Reaching for a microphone, he spoke over the P.A. system.

"They've also turned up the music on the P.A. system so it's much louder than normal."

The door hardly closed behind them when an important announcement came over the ship's P.A. system.

Create a working P.A. system that can relay messages throughout trains and stations.

He doesn't answer him but instead he's switching on the P.A. system and is giving out instructions.

It shouldn't take much of the money to send a team through each subway station to make sure that every P.A. system works properly.