MediaSlap blog

In the same sense of not needing to know the chemical makeup of the ink to use a fountain pen, this article offers some important considerations in audio post production that can make the difference in your product sounding professional or amateur. One of the most common requests made of sound editors is to “clean up” the dialogue. The process used to accomplish this depends on what issues the soundtrack has to overcome. While the removal of clicks and pops may be relatively easy, the more complex removal of background hum, noise and ambience may be required.

Location Sound

On location, TV and film projects utilize a shotgun microphone on a boom for long shots, while many close up shots use a microphone hidden on the subject. Both recording methods bring challenges to audio post production. The difference in sound quality between the close up shots and long shots must be matched as well as the varying backgrounds, unless the sound is recorded in a “controlled environment” like a sound stage. But even if the dialogue to be matched is from two different close up angles (like over the shoulder shots for a conversation), the general ambience differences may still be extreme. Hum, mouth noises and background noise should be removed or reduced.

ADR & Dialogue Replacement

ADR process described by Director Peter Masterson and Actor Gene Hackman during dialogue replacement for “Full Moon Over Blue Water” ~ 1988.  Although the process has not changed the technology is now all digital. Sound Works has been doing ADR since the mid 80’s.

Sometimes the location sound is distorted so badly that the director may be tempted to start over and re-shoot the entire scene from scratch. Given the cost of a production crew, location costs and rentals, this may not be the most cost-effective solution. ADR can be an effective solution for replacing individual lines. It requires the skill of the actors and ADR engineer to match the performance and sync. The engineer has a number of tools to assist with ADR. For example, Sound Works has software that will lock-step the sync of the new performance to the original recording allowing the actor to concentrate on expressing the line properly. In post production, the qualities of the performances can be matched in tonal quality and proximity to the camera. The voice “tone” is adjusted to make the voice more “up-front” for the close up reads.

Background Sounds

Location sound engineers should always record background ambience to allow the audio post people more options when matching dialogue. For example, if ADR is to be used, the re-recorded line will have little or no ambience compared to the replaced location line. But the previously-recorded location ambience can be added to the ADR sections resulting in a seamless-sounding dialogue track.

But let’s say the shot is at sundown and the volume level of crickets in the background is changing every 30 seconds. It is possible to sample the undesired crickets and peel them out of the sound track leaving the desired dialogue unaffected. At Sound Works, we have several processes to remove or reduce background noise. This is the same process used in our forensic audio service. Removing undesired background noise could eliminate the need for ADR or reshooting the entire scene. And THAT makes the sound editor’s job one less headache!