"I sing in the car if I'm in LA, because you're like soundproofed"

Jimmy Fallon is referring to the reality that when he is driving in Los Angeles, he feels comfortable enough to sing in his car. This is since the cars in Los Angeles are soundproofed, implying that the noise of his singing will not be heard by anybody beyond the car. This is an excellent method for Jimmy Fallon to reveal himself musically without stressing over being evaluated or humiliated. It also permits him to delight in the music he enjoys without needing to stress over the sound bothering anybody else. By singing in the cars and truck, Jimmy Fallon is able to take pleasure in the music he likes without having to stress over the sound troubling anybody else. This is a great way for him to reveal himself musically without worrying about being judged or humiliated. It also allows him to take pleasure in the music he likes without having to stress over the noise troubling anybody else. In General, Jimmy Fallon's quote is a fantastic tip that it is fine to reveal yourself musically, even if you remain in a public location.