Loudspeaker cabinet construction with directive characteristic - has matrix of holes passing through back wall with lattice dimension equal to twice cabinet depth

摘要

A loudspeaker cabinet yielding a desired directive characteristic has a speaker (Z) mounted in its front face. The enclosed volume of the cabinet (Co) communicates with the cabinet exterior through a rear plate matrix which consists of a thick plate with a rectilinear array of through holes. The rectilinear array of holes (M2) is backed by a layer of acoustic damping material (R2). In order to achieve the desired directive characteristic the overall dimension of the array should optically be equal to twice the cabinet depth (d), however it may be as small as (d/2) a half the cabinet depth (d).