Abstract
When two parts of sound space are connected by opening sections, resonant frequencies and the peak level at the frequencies change greatly according to the size and shapes of the opening sections and the acoustic pressure. Then, two rectangular parallelepiped sound places are shown by the sine wave function that fills the wave equation. The opening sections are expressed by transfer function considered as a perforated panel and the two sound places are connected with opening sections. The validity of the proposed calculation method is verified by comparing the math calculation with the experiment.
