Sound, half of the experience.

George Lucas once said: "I feel that sound is half the experience. Filmmakers should focus on making sure the soundtracks are really the best they can possibly be because in terms of an investment, sound is where you get the most bang for your buck"
Sound is definitely half of the experience, it is so important that can completely change the meaning of what we're seeing in the screen.
According to the text, sound in cinema is primarily vococentric, it always privileges the voice, because who's watching the film is mostly concerned to understand the words, to familiarize with the context, to absorb the meaning of what the actors are saying, and after he's completely comfortable with it, then he starts to pay attention to the background and the sounds surrounding it. The ear analyzes, processes and synthesizes faster than the eye, that is the reason the sound is deeply explored in film, like in an horror movie when you feel completely tense not because of what is showing in the screen, but for the soundtrack is playing; also because in an horror movie usually the action scenes contains fast cuts and camera movements, which also takes more time for your eye to acknowledge everything that is happening. The eyes perceives more slowly because it has more to do all at once.