Well, it's more individual than anything, but my Ameraucana and my Buff Orpingtons are probably my quietest girls. My Rhode Island Reds and my Wyandottes are the loudest.
My grandmother has some leghorns. I wouldn't say they are noisy in general but they are flighty. If you go in the coop they run around like crazy.
My leghorns were only noisy when I went in the coop or run, they would squawk and run around and fly and generally act like I was going to catch and eat them right then and there. Silly birds! But they did lay a lot of eggs.
I have two leghorns and they are very noisy .One has a very loud song she sings before she gets in her lay box but they are good birds.