a wire communication system that permits an enterprise manager (the chief operator) to carry on conversations directly with subscribers (subordinates) and to make group conference calls. An individual call or a group call with 20 to 50 direct subscribers may be made through the chief operator’s switchboard, which also has an automatic telephone station outlet; conversations may be carried on through the chief operator’s switchboard both by means of a reversible dynamic loudspeaker and through a hand microtelephone set. The chief operator’s switchboard often has a visual (light) signaling system and may also include a magnetic recording device for taping conversations.