Automated Dialogue Replacement (ADR) is the technical term for a process sometimes conflated with dubbing. It is used by filmmakers to rerecord dialogue after principal photography has been completed. However, it is a more precise term than "dubbing", which has many separate connotations, including the use of different actors to record the dialogue in another language. ADR is thus a process used to achieve the final audio track of the original version of a work. Other synonyms include Additional Dialogue Replacement, looping and, chiefly in the UK, post-synchronisation.
The general reason for needing to perform ADR is because of interference by background noise captured while a scene was recorded. Alternative reasons include a need for better stereophonic separation or simply better enunciation on the part of the actor. Occasionally, entirely new lines (such as narration or a correction to a scripted line) might be required.
All post-JNT versions of televised Doctor Who have made extensive use of ADR, as it has become standard filmmaking practice to re-record dialogue. Additionally, lines which are treated with vocal effects are now often dubbed back into the audio mix after a special ADR session. This technique was hardly used at all during the monochromatic era of Doctor Who, and was generally too expensive for even colour Doctor Who budgets to bear. Even "treated" voices, like those of the Daleks, were often captured live by the same microphones covering the main actors. Nevertheless, ADR was sparingly used, largely when there was no other choice.
A good measure of the importance of this craft can be gleaned from the credits. In the original series, the closest credit to ADR is that of "special sounds" — mainly describing foley work — attributed to Brian Hodgson from An Unearthly Child to The Sea Devils; and to Dick Mills from The Mutants to Survival. However, the BBC Wales production specifically tasked individuals with ADR production. Paul McFadden was credited specifically as dialogue editor during series 1 and continued on under other titles as the main member of the sound department tasked with producing ADR sessions.
- "I don't enjoy recording ADR — which is no secret to the people who have to record it with me. I find it difficult and frustrating because you're not there. You're not in that moment anymore. You're not looking that actor in the eye. You're not experiencing that story in the way you experienced it on the day that you shot it."