In this paper we study the suitability and performance of four major speech denoising algorithms as GCC weighting functions and discuss the role of the microphones' frequency response on the localization estimates. An evaluation is made with the humanoid robot Nao. Moving away from simulated environments, we look at the performance of sound source localization under different in-system and ambient noise conditions. We also present a TDOA/GCC based sound source localization method for real-world humanoid robots which was used for our experiments. This method addresses the robot's shape influence by utilizing a pre-measured set of TDOAs.