ATUC-50DU discussion unit is equipped with a 3-pin XLRF-type input for use with compatible gooseneck microphones, including the ATUC-M43H or ATUC-M58H microphones specifically designed for the system. The discussion unit also features a display for monitoring volume and channel selection, buttons for selecting channel, a built-in speaker, a headphone jack with volume control, two independently programmable LED indicators, and a talk button to turn the connected microphone on/off or send a request to talk to the moderator. On units designated by the control unit as priority discussion units, the talk button can be used to mute and override a non-priority discussion unit. Up to 50 discussion units may be connected to a control unit, using Cat5e (or better) cable employed in either daisy chain or ring topology. Ring topology offers an additional layer of stability to the system since the system actually regards the start and end of the ring (terminated at the discussion unit chain A/B inputs on the control unit) as the start of two daisy chains. Thus, even if there is a connection failure somewhere in the ring, the control unit will still recognize each discussion unit as part of one of the two daisy chains, allowing the system to function without interruption. The discussion units are designed for tabletop or recessed mounting, and are outfitted with a paintable front plate.