Interruptible foldback

Interruptible foldback (IFB), also known as interrupted foldback or interruptible feedback, is a monitoring and cueing system used in television, filmmaking, video production, and radio broadcast for one-way communication from the director or assistant director to on-air talent or a remote location. Less common names for the system include program cue interrupt (PCI), switched talkback and interrupt for broadcast. IFB is often facilitated using an earpiece that on-air persons wear to get cues, feedback or direction from their control rooms. The earpiece itself may also be referred to as an IFB. Sometimes IFB is accomplished by the director talking to off-camera personnel who visually cue the on-camera talent.

The IFB is a special intercom circuit that consists of a mix-minus program feed sent to an earpiece worn by talent via a wire, telephone, or radio receiver (audio that is being "fed back" to talent) that can be interrupted and replaced by a television producer's or director's intercom microphone. On a television news program for example, a producer can talk to the news anchors, to tell them when they are live on the air and when to begin reading off the script on the teleprompter or cue cards. In live television, some news anchors are seen listening to IFBs in order to report breaking news and announcements.

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