Effective control point layout for boundary surface control method based on the eigenfunction of the internal Dirichlet problem

The boundary and additional-points sound pressure control (BAPC) method was proposed. To verify the sound field reproduction performance of BAPC, a rectangular enclosure of 2m × 1:3m × 0:1m based on the Nelson and Elliott's acoustical model was assumed. The additional control point of BAPC is located at the center of the control region, where there are no nodes of eigenfunctions of the internal Dirichlet problem. The total number of control points is set to 25. The sound source layout is selected from 132 positions on the rigid wall at 0.05m intervals by the Gram-Schmidt orthogonalization method and the number of sound sources is set to 26. The control point layouts determined by this tactic showed about 2-3 dB better performance than those with uniform distribution with the same number of control points of eleven.