This academic configuration consists of two fluids (water and oil) separated by a plane interface. Ellipsoidal inclusions filled by vacuum or solid diffract the compressional waves created in the fluid by two source points. The 4th order ADER scheme associated to 3th order ESIM immersed interface method is run on a 600x600 cartesian grid points. Computational domain is surrounded by a PML layer. High quality propagation, diffraction and conversion of waves are observed.