Sound Analysis

Sin City Film Opening
Ambient Sound- Car horns, sirens in the distance and the general bustle of the big city create a soundscape for the location the scene is set in.
Synchronous Sound- seeing her walk and hearing the sound of her heels on the concrete. Him walking towards her and hearing his footsteps. The lighter and the sound of a flame lighting. The gun shot with silencer, then seeing the gun. The rain and the sound of rain falling on the concrete.
Symphonic music- the sound of saxophones and other horn instruments.
Voiceover- the male character in the film narrates his thoughts on the scene that is unfolding on screen. Adds to the ambiance and helps the audience understand the storyline a little more, as you get insight into the character and his questionable actions in this opening.
Asynchronous Sounds- the sirens and the noise from the streets below.

Diegetic
Or
Non-Diegetic

The music is subtle enough that you hear it, but it does not distract or compete for your attention with the dialogue and voiceover. The voiceover helps establish the narrative and the character further, thus aiding the audience in understanding the genre of the film.
The soundscape created of the city aids the audience in gauging the atmosphere of the opening scene. The car horns, the sirens and the bustle of the streets below amount to the overall soundscape of a busy city in America, somewhere like New York or Chicago.