Synchronization of background noises. Background noises, as the name suggests, are intended to convey information about the environment. Background noises itself represent audio textures such as the rustle of foliage, traffic sound of an international highway, or urban background.
Types of noises
Depending on how the noises are combined with the image they are divided into intraframe and offscreen. Synchronization is required as a rule only for intraframe noises. The process of recording and editing differs in both types of noises.
If an action takes place on the screen, other noises may sound in the background. Such noises would be called second-order noises. In most cases, second-order background noises do not require synchronization.
For example, in the foreground, the man approaches the car and begins to open it with keys. The sound of the lock and keys will be tied to the main action and of course, requires synchronization with the video. This is a typical example of intraframe noise. In turn, city noise, which can include the sounds of cars moving along the highway, is second-order background noise and does not require synchronization.
In order to convey maximum information about the space, it is recommended to record background noises in stereo mode. It is best to use several microphones located in different places when recording. Then during editing, you could combine sounds from different tracks to get the desired spatial picture.
The choice of the location of the microphones determines such parameters as the width of the stereo sound, the accuracy of the localization of sound sources, the frequency spectrum of the recording, the balance of the middle and edges. The closer the microphones are to the sound source, the more vivid and transparent the timbre will be. At the same time, too close a distance to the object worsens the spatial picture. The search for the optimal position for microphones is always about a compromise.
Create the right mood
Ideally, background noise should not distract attention from the action on the screen. It is intended only to create the right mood. To achieve this goal, it is necessary to exclude any regularly repeated sounds. Such elements of the sound picture are very noticeable and can cause irritation in the viewer.
At the same time, long-sounding background noises can carry a certain semantic load and create the right mood. For example, the smoothly growing rumble of an avalanche and falling rocks can create a sense of threat for your viewers. Noises affect the emotional state of a person. The maximum immersion of the viewer in the picture is possible only when he does not feel deceived and experiences emotions.