OK, I have a question for you first. Are you smelling the whole cone or did you split one in half? Split one in half if you haven't and take a whiff. You will also see the lupulin glands in there, they should be about school bus or traffic line yellow.
Secondly, you don't want to gauge when they're ready by how brown they are. A little brown is OK, but none is better. They would be ready once they get kind of papery feeling. You know, like feeling dry.