The digital discussion central unit ADN CU1 powers and controls up to 40 (depending on cable length) connected delegate and chairperson units. It offers full configuration in a quick and easy way over the menu display in several languages. It offers full configuration in a quick and easy way over the menu display in several languages. Alternatively the integrated software package 'Conference Manager' can be used directly on the CU1 by connecting a screen, mouse and keyboard. The intuitive workflow of the conference manager allows a fluent monitoring and control of the conference. With its low-noise fan the central unit can be used directly in the meeting without disturbing it.