The role of music in filmmaking. Essentially its primary role is storytelling. Driving the narrative along through a variety of moods. Scene setting. Building bridges between interviews, stock footage or animated sequences. In fact, for the majority of the program, the music is playing a secondary role to the voice over. Only taking centre stage for brief moments before the voice returns to the forefront.
Therefore it’s important that your music creates the required mood within around 4 to 8 bars (perhaps 8 to 10 seconds) as the scene is set and the narrative prepares for the change of pace. You may choose to use a section from another part of the tune when the instrumentation has built in pitch or reached a crescendo. Therefore it’s always good to listen through a track you think may be suitable to make sure you are utilizing it to its full potential.