Sound Design involves adding in sounds and taking away sounds from your final movie track. This is done through adjusting the volume of the actors voices, adding in background noise, adding in sound effects and adding in a soundtrack.
Adjustments to the Actor’s Voices
Even though you have had someone mixing individual channels of you actors on set, there are still going to be times in the film where you need to adjust the acting voices in post. This usually happens as your sound designer watches the movie and helps to enhance dialogue that may not be able to be heard otherwise.
ADR or Automated Dialogue Replacement
There can be points in you film where a noise in the background has caused your actor’s dialogue to become unusable. In this case you need an ADR session. What happens is you bring your actor in for basically a voice over session to rerecord the lines that are unusable. In most cases you will set up a monitor for your actor to watch so that they can follow their exact lip movements and you can dub in the new audio seamlessly.
Background Noise and Sound Effects
After you edit your film and have your final master, you will want to add in sound effects suck as the creak of a door or birds chirping in an outside scene. The good thing about these effects is that most of them will already exist in an audio effects file and can just be dropped into the film effortlessly.
Soundtrack or Musical Score
A soundtrack is the final polish that any movie needs to be complete. There are many canned soundtracks that can be purchased and added to your film but in my opinion, nothing beats an original score and these are not as far out of reach as you may think. The trick is finding someone who composes music and wants to get into film scores. If you find the right person, they will usually compose the film for you at a discounted rate to be able to score their first film.