Cleaning up sound in my short film

In editing my short film, I spent a lot of time on sound. Good sound is imperative in any film if it is ever going to be taken seriously. A film can have bad sound but be shot really well and be called amateur. However, if a film has really good sound but is not shot very well, it is more likely to be taken seriously and called “artful.”

In order to get good sound, it’s important to consider it on the front end and use a good boom mic. However, this is not enough. There will almost always be some background noise that you didn’t catch during shooting (usually the refrigerator). It’s also difficult to match up dialogue, not because of syncing it up necessarily, but because of different noises that are in each take.

The first thing you need to know is to ALWAYS GET ROOM NOISE. Room noise is in strict definition “the sound of a room.” Before you finish shooting in one location, always get at least thirty seconds of room noise so that you can make each cut more seamless in post.

In my film, my characters were talking in a car at one point. I had different takes of each character that I needed to match up. What made this difficult was the constant change in tone of the car and the engine. Sometimes the car would be going fast, slowing down, turning, not turning…it was always different. To help mask this, I recorded the sound of the car while driving at a constant speed and laid that under the dialogue. I then put a high pass filter to help eliminate the rumble of the engine. Doing these two things eliminated or helped mask a lot of the noise in each shot. One last thing I did to help mask each cut even more was using L cuts — cutting into the audio before cutting into the picture or vice versa.

In a another scene, I had a long moment of silence. However, as is usually the case, the microphone picked up an unknown, but undesired, frequency. To get rid of this, I initially just EQ’d the frequency out of the mix, but as a result cutting out that frequency basically took out all of the room noise. The scene would fall completely silent. To fix this, I just completely took out that audio and inserted about 5 seconds of room noise from another shot that didn’t have that undesired frequency and repeated it underneath the whole scene. This is a helpful fix if for some reason you forget to record room noise.

I hope my experience with cleaning up sound will help you out in some small way.