As a result, facility planners now view digital systems more favorably, a trend found in large facilities as well as smaller studios, which once relied on extended multiconductor cables 2-wire systems. Communication may be half or full duplex. A 4-wire intercom circuit transmits audio on one pair of wires and receives on a second pair. Instead of subsystems to achieve different functions, the central processor and software permit the system to be dynamically configured for different forms of communication. Audio signals carried by either system structure individually should be of sufficient quality for on-air work, if the necessity arises.
Some applications do use the intercom for program audio.
However, when the two structures are brought together, problems can arise. In particular the quality of the two wire equipment can exhibit degradation from 4 to 2-wire conversion hybrids used in the two wire station. Also, operating levels may be different from one brand and system to another. Some means to compensate for differing house reference levels is necessary. Multifunction 2-wire intercom systems require distributed subsystems for each task.