I had 11 Brown Single Comb Leghorn sent "as warmth". We chose one to keep and around 16 weeks he started trying to crow. The others wouldn't even try. Moved them all out to their pens and had about 6 start crowing. We could tell which one by his crow all where different. My Partridge Rock ( the only rooster I ordered) wouldn't crow and barely made any noise until after all the hens started laying at 23 weeks old. And man does he sound weird. If you couldn't see how big and pretty he is you would think he was......... well you wouldn't think it came out of him. I just laugh every time I'm out there and he starts crowing it is very, very funny. I have two SLW and they haven't crowed yet. All of our chickens are within a week of being the same age all where hatched in Feb.