Halogen provides another useful block: the Conference Switchboard, demonstrated in the figure below. This example configuration has three rooms co-located in a building that from time to time need to conference with each other. Further, any combination of rooms may want to participate in a conference at any given time. This example does not necessarily use VoIP or other Telephony between these local rooms, as these add unnecessary delay and can degrade sound quality compared to a direct connection.
You could accomplish the required routing with a matrix mixer, but doing so requires ensuring paired From-Far-End and To-Far-End routing for each room. This is difficult to do without setting up complex presets to adjust multiple matrix mixer levels and/or cross-points simultaneously. In addition, it is highly desirable to create intuitive system controls for the end-user, which is difficult with the matrix mixer approach.
The Conference Switchboard solves these problems in an elegant way. Each Room has a From-Switchboard and To-Switchboard connection with the Conference Switchboard block. If a user is in the Green Room she simply selects conference participants from a list. A DR remote, a Web Control, and/or a 3rd-party control system can provide intuitive control for her to make this selection. In the example shown below, the Green Room user has selected Blue and Amber rooms for a conference. The Conference Switchboard supports up to 32 channels in any combination of room and telephony participants.