Music can bring people together, make them dance and equally make them cry. It’s the composer’s job to accompany the film by using music.
Through music mixing software it’s the composer’s job to write and create music following the director’s image. This music will comprise the soundtrack of the piece and can help transition from scene to scene. It’s important to have a grasp of genres of music and how to use them, such as looking at what instruments can be used to fit different tones.
Being able to listen and understand how different theme songs and intro music can affect the tone of the piece from catchy game show jingles and stings to dramatic high action beats to follow a detective to the scene of the crime.
Understand music theory
Know how to mix sound elements
Understand the stone / vibe of a piece
Communicate to the director what the creative image is.