The Power of Ambience:
Don’t Overlook This Key Ingredient in Sound
Written by Bryant Falk
When recording sound for film and video, more often than not people overlook a few key ingredients that could allow them a painless editing process in post. One ingredient is ambience. This audio is typically the kid forgotten at home while everyone else travels across the world to have fun.
Simply put, ambience is the sound of a location when there is no sound. ‘No sound’ being no dialogue. Locations include: Coffee Shops, Libraries, Schools, Restaurants, etc. Even ‘outdoors’ has an ambience. An example is shooting a scene near a parkway for instance. On a smaller project it may be cost prohibitive to shut the parkway down and choreograph all the cars traveling through the scene. Better to capture five minutes worth of the ambience so you can have options when creating continuity within the scene. Ambience also pushes the reality of a moment. Feeling the location around your actors can be invaluable in pulling your audience in.
Another plus in recording ambience is to help remove it. Today’s digital audio systems allow many ways to remove noise. One way is to play a selection of ambience into your noise reduction software, so it learns what you want to take out, and then, apply it to the audio you’re cleaning. Another way is to reverse the polarity of you’re clean ambience and mix it into the source you’re trying to minimize. Reversing the polarity of an audio clip can be looked at like a mirror image. It looks the same, but if you try to read something the words are backwards. In audio if you look at two audio waveforms with one being the reversed polarity, they will look exactly alike but exactly the opposite of each other. Mixing these two in varying amounts may achieve a quieter ambience track should the original be too overwhelming.
One more power of ambience that is effective is using it as an emotional adjuster. By adjusting the pitch through time and adding effects you can use ambience as an indicator that something is just not right in your scene. Whether it is an emotional turn between two characters or the need to increase dread at the fact the nightmare character in the closet is about to spring out.
I always recommend cataloging ambience after you’ve finished a project. There may be more than one occasion when someone yet again forgets to record ambience, and the one you already have may work just right.
Bryant Falk has been a producer and engineer for over 12 years working with such clients as The Ricki Lake Show, Coca-Cola, Sports Illustrated, Valley National Bank, and MTV’s The Shop. His company Abacus Audio (abacusentertainmentnyc.com) handles many aspects of the audio production field from creative and production to mixing and final output.
(The Power of Ambience in Audio)