Now that I have finished to talk about the kind of songs which we usually find in a movie, let’s talk about the different layers of music in any given movie. There are different possibilities to add music to a movie. In every given moment, you can add music either from the off or in-scene. And if you pick in-scene, you can decide between justified or not-justified.
Whenever music is played from the off, it is like there is someone commenting the movie for you, either through music or song, manipulating the emotions of the audience and the way a scene is perceived. This is the most common choice in any given movie, because the right music can elevate a scene considerably. Just imagine the shower scene from Psycho without tone. Would it be as iconic as it is nowadays?
Justified basically means that the music happens in the scene itself for a realistic reason. The radio is playing in the background, someone is on the stage and sings, whatever the reason is, the audience knows where the music is coming from and perceives it as part of the scene.
Having not-justified music in scene, which often results in putting music at the very forefront. Usually music is used to underline a certain mood, but in some cases, the audience is supposed to pay attention to the music first and foremost, which is often achieved by combining singing in-scene to a melody from the off (though it naturally also works the other way around). That is the kind of music you’ll find mostly in musicals, when the characters are starting to sing in scene to a melody which is played from the off, requiring a certain level of suspense of disbelief from the audience. Naturally they are exceptions to the rule. For example a lot of songs in “Chorus Line” are technically justified since the musical is about a Broadway production.
But weather in-scene of from the off, there are three possible choices of music: An underscore, a song or silence. Silence is actually the choice which is most often picked, because the moment you decide to have music on one level, it is very likely that your choice for the other levels will be silence. As example, let’s take a look at Disney’s “Bella Notte” scene:
The scene starts out with an underscore from the off, while the choice for in-scene is silence. Then, a 0:20, suddenly the accordion interrupts the underscore, switching from music from the off to music which is played in-scene. Now the off is silent. At 0:23 the singing starts – but the music is still fully justified. Until 1:35, when the scenery changes. Now in-scene is silence, and we are back to music from the off, but this time around it is not an underscore, but a song.
It might sound strange to call silence a choice, but consider how loud silence can be. For example the scene when Bambi’s mother dies. The sudden shift from happiness to danger, the flight through the woods, all this is underlined with an underscore which amplifies the shift in the mood. When Bambi calls out for his mother, a chorus is singing from the off, already suggesting her fate. But the moment his father turns up and tells him that she wont be back, there is suddenly total silence. No score, no singing, just this deep voice telling Bambi that he will never see his mother again.
There are naturally other choices one can make concerning music: Original or pre-existing music, the different style, a song with one singer or a chorus, just to mention a few. But from the off or in-scene, justified or not, underscore, song or silence, those are the most basic ones.