Room Eigenmodes Calculator
This calculator determines the room eigenmodes with the 20 lowest eigenfrequencies for rectangular rooms and presents them in ascending order. To distinguish between the different eigenmodes they are designated by a combination of three natural numbers. In the calculator they are listed in columns nx, ny, and nz of the table. The indices x, y, and z indicate the direction in space the numbers refer to. You would, for example, speak of room eigenmode (1 2 1).
Each eigenmode is associated with a different sound pressure distribution. The isometric representation of the room in the calculator shows the square value of the sound pressure at the walls of the room. Dark areas correspond to a high sound pressure or high loudness.
In order to achieve good acoustics it is desirable that the eigenfrequencies are uniformly distributed, and that no accumulations occur near to a particular frequency. A coincidence of eigenfrequencies occurs whenever one dimension of a room is an integer multiple of another such as, e.g., in a room that is twice as wide as it is high.