  In the famous work by Buff and Ch\'eritat constructing quadratic Julia sets
with positive area, the control of the shape of perturbed Siegel disks is a key
technique. To do it, Buff and Ch\'eritat added a restrictive condition on
rotation numbers. In this paper, we show that this restrictive condition can be
deleted. As a consequence, more quadratic Julia sets with positive area can be
constructed.
