Non-axisymmetric and horn-free phase plugs [70] and related audio devices [100, 200] include various compression members [2] such that central axes [93, 99] are defined perpendicular thereto; and such that a guide [120] extends from a compression member [2] to a phase plug tip [84], wherein the guide [120] is non-axisymmetric to the central axes [93, 99].