Convention Paper
Mutual Radiation Impedance of a Double-Disk Source and Its Effect on the Radiated Power
AES Convention 76 · Paper 2144 · October 1984
Abstract
The acoustical interaction between two disks in an infinite baffle is discussed in terms of the mutual radiation impedance. The mutual radiation impedance is calculated for several different source geometries by numerically evaluating the Rayleigh integral. Then, its effect on the radiated power of a two-way system with various Butterworth crossover networks are evaluated. When the two disks vibrate in-phase, the increase in efficiency at the crossover frequency is less than 3 dB (which is achieved only in an ideal case) because of the increased size of the source. When the two disks vibrate +/- 90 degrees out-of-phase, the total radiated power is equal to the power radiated from the two disks without the interaction. In this case, however, an excessive power is radiated from one disk and the same amount of power is absorbed by the other disk.
