public address system vs talker

public address system

noun
  • An electronic voice-amplification apparatus, usually containing a set of two loudspeakers and a central control unit, used for singing, giving a speech, play-by-play commentary at events, or broadcasting in public areas like in airports or stations. 

talker

noun
  • A stripped-down version of a MUD which is designed for talking, predating instant messengers; a kind of early chat room. 

  • A talk-show host. 

  • Mouth. 

  • Any creature or machine that talks. 

  • A talking point. 

  • An all-talk radio station. 

  • A popular topic of conversation. 

  • A person who talks, especially one who gives a speech, or is loquacious or garrulous. 

  • A talk show 

How often have the words public address system and talker occurred in a corpus of books? (source: Google Ngram Viewer )