I lived at the intersection of Córdoba and Pueyrredón for 6 months, facing Córdoba. Great, central location but the noise of sirens and traffic constantly was so intense, even on the 12th floor, that it eventually faded into white noise that we stopped noticing. I would Skype with my mom and she would wonder what was happening outside, and I would always have to tell her that was what things always sounded like.
After that I lived at two quieter places, both older buildings where the unit was close to the back of the building. It was totally worth not having much of a view. Now I live across the street from a boliche at a fairly busy intersection where the light is frequently broken and there is at least one crashing car accident each week. I thought, if I have to hear one more techno rendition of Katy Perry's "Firework" I am going to scream. But luckily I brought two types of earplugs back from the U.S. and they are magical. I know they're uncomfortable at first, but just keep trying because once you get used to them you will never go back.