I aimed at a design, which is expected to be high-quality sound only by the first sight at its appearance. I formed a body that adapts itself to the hand and provides simple remote control operation. It is a simple portable headphone amplifier developed for the purpose of enjoying a high-resolution sound source easily. Since body size was minimized, a battery was not built in, but the bus power system, which receives electric power supply from connection apparatus, was adopted. All appearance parts not referring to a clip were deleted from the lump of aluminum.