Comment on "Theory of tailoring sonic devices: diffraction dominates over refraction".

Recently, Garcia et al. [Phys. Rev. E 67, 046606 (2003)] studied theoretically several acoustic devices with dimensions on the order of several wavelengths. Those authors also discussed experimental results previously reported by several of us [Phys. Rev. Lett. 88, 023902 (2002)]] and concluded that it is diffraction rather than refraction that is the dominating mechanism explaining the focusing effects observed in those experiments. In this Comment we reexamined their calculations and discussed why some of their interpretations of our results are misleading.