An information processing technique for voice outputting an electronic mail, received by an information processing apparatus capable of voice output, at a sender’s intended timing. Each employs a naturally occurring, non-porous igneous rock material, such as granite, that may be configured in the form of a polyhedron, such as a cube. The method is particularly suitable for high levels of nonlinear signal distortion, and ensures compensation for and optimization of the qualify parameters for all the channels at the transmission path end. Ink remaining on the nozzle surface is absorbed by the absorber. A helically extending groove is formed in the middle of the central part of the bottom surface. A related manufacturing method includes selecting the positioning mark in accordance with a predetermined resolution and anchoring the anchoring plate to the base plate so that the reference mark and the selected positioning mark are in the same relative positional relationship.