A modification of the reflective array method is proposed based on the assumption that the transduction part is spatially separated from the mechanically reflecting part in an arbitrary electrode structure. The electric potential of an electrode is determined by the charge distribution over the whole structure and electrical potentials of locally incoming waves, while the outgoing waves are determined by the local charge distribution. The wave potentials in neighboring electrodes are related through expressions of mechanical reflection. In this way additionally to the electrostatic part of the total matrix of the problem the wave part is obtained. The approach is selfconsistent and automatically takes into account electrical reflections. Significant acceleration in simulations is achieved, because the electrostatic part of the matrix is frequency independent, while the wave part is derived from additional quasi-diagonal intermediate matrices.