Express Paper
Boundary conditions of the dome compression chamber in horn drivers
AES Convention 153 · Paper 46 · October 2022
Abstract
Previous publications on the acoustics of the dome-shaped compression chamber assumed the Neumann boundary conditions (zero velocity) at the periphery of the chamber. In this work, three configurations of the compression chamber having different boundary conditions are analyzed. In one of them, the chamber has a Neumann boundary condition. In the second configuration, the compression chamber is loaded by the voice coil gap. In the third configuration, the compression chamber is positioned on the convex side of the dome, and the air cavity above the surround is an extension of the compression chamber. For the dome-shaped chamber, the solution was searched in spherical coordinates as an analytical presentation of the Legendre function by the Mehler-Dirichlet integral form. In the second and third configurations, the impedance of the voice coil gap and the air cavity adjacent to the diaphragm’s surround was approximated analytically.
