The seat dip effect (SDE) is a low-band attenuation phenomenon that occurs in the music halls when the music sound passes at a near grazing incidence over the seats, and the SDE is different from the seat sound absorption. In this paper, the visual computer simulations on the basis of finite element analysis are used to study the characteristics of the SDE and the influence of seat attributes on the SDE. This study visualizes the relationship between the dip frequency of the SDE and the seat height and seat spacing in intuitive visual graphs for the first time. Results indicate that increasing the seat back sound absorption or cushion sound absorption can effectively reduce the SDE.