How Audio Post Production Works

Audio Post Production Systems and Software

Sound engineers combine a film's dialogue and sound effects in a post-production studio.
Sound engineers combine a film's dialogue and sound effects in a post-production studio.
© Piotr Powlietrzynski/Photographer's Choice/Getty Images

Film and TV editing is an entirely digital world. No one sits around splicing film stock anymore. Even if a project is shot on film, it'll be digitized for editing and laid back onto film for distribution. The same is true for audio post production. The nice thing about digital audio editing technology is that there's a product and system for every budget and skill level.

For the home studio, everything can be done on a single computer without fancy control panels or consoles. You can buy a basic version of Pro Tools, Adobe Audition or a similar digital audio workstation (DAW) and do all your recording, editing, mixing and exporting using the software's built-in functionality. Pro Tools doubles as a MIDI (Musical Instrument Digital Interface) sequencer, so you can even record a soundtrack straight into the software using a MIDI controller or live instruments.

Professional audio post production studios add another level of control by using large digital editing consoles. All of the knobs and faders on the console control specific elements within a DAW like Pro Tools or Nuendo. For many editors, it's faster and easier to manipulate knobs and faders by hand than to constantly be reaching for the mouse and keyboard.

Here are some features of DAW software for audio post production work:

  • Handles an unlimited amount of separate tracks for the same project. This is especially advantageous in mixing a big project with different Foley recordings, sound effects, dialogue, background noise, music, et cetera.
  • Tracks the audio to a built-in video feed. This is critical for timing the placement of effects and music.
  • Allows for tons of different automated pre-sets. Each separate audio recording session requires different levels on each track to create a balanced recording. DAW software makes it so you only have to set those levels once. Once they're saved as pre-sets, you can just click a button and return to the desired settings. This works with the large consoles as well. Click a button and all of the knobs and faders will return to where they were two Wednesdays ago.
  • Cleans up bad recordings. Maybe a plane flew overhead when your hero was saying his big line, or the air conditioning unit in the grocery store was buzzing too loud. DAW software includes special filters and tools for cleaning up clicks, pops, hums, buzzes and all other undesirable background noise.
  • Endless plug-in options. Plug-ins are small software add-ons that allow for additional tools and functionality. They can be special effects plug-ins, virtual instruments for scoring a movie, or emulators that reproduce the sound of classic analog instruments and equipment.
  • Graphic interfaces for placing sound recordings in the 5.1 surround sound spectrum. By moving a cursor back and to the right, you can make it sound like a train is approaching from behind the audience.

And what's the deal with THX, Dolby Surround Sound, DTS, Ultra-Stereo and all those other fancy terms? THX is a standard developed by George Lucas to ensure that how a film sounds in the studio is how it'll sound in the theater. Both soundstages and theaters can be THX certified. The rest are technologies for encoding a film's final audio, and each requires the purchase of a special license. Different encoding technologies allow for more surround sound channels and apply to either optical or digital soundtracks (for more details, check out How Movie Sound Works).

For more information on audio post production and related topics, check out the links below.

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