Audio response unit

In telecommunication, an audio response unit (ARU) is a device that provides synthesized voice responses to dual-tone multifrequency signaling input by processing calls based on (a) the call-originator input, (b) information received from a host data base, and (c) information in the incoming call, such as the time of day.

ARUs are used to increase the number of information calls handled and to provide consistent quality in information retrieval.