I don't know if this helps very much because I think that everyone's experiences are different, but I have both cochin and silkie roos. In my experience, the silkies crow ALL THE TIME. Well, this might be a little exaggeration, though sometimes it seems that way! Anyhow, their crow is pretty shrill and quite loud. I love them though (my husband does not!) so I tolerate the noise, make excuses for them to my husband, and am continually grateful that my nearest neighbor is out of ear shot! The cochin boys, in my opinion, are much more laid back and have a lower pitched crow that is much easier on the ears. My friend had a cochin roo, too, and often remarked how seldom he crowed and that it was much lower pitched and easy on the ears compared to other roosters she'd had! I love all my boys, but agree that the smaller they are the more annoying the crow is. I also agree that it would help to only keep one rooster if the crowing bothers you as they kind of feed off of each other, getting a real crow-fest going sometimes!