An optimized form of a two-magnets coil system (TMCS) has been explored and analyzed experimentally. This device has larger spacer of 3 cm compared to our previous devices, thereby a lower recalling magnetic force occurs inside the center of the windings and the magnets can move more freely along the axis. This process enhances the displacements of the magnets and generates more powerful outputs. In addition, the mechanical excitations at low frequencies become more obvious compared to our previous system. The power density of 20.487 μW/cm3 has been achieved for the new designed electromagnetic harvester. The maximum peak-to-peak voltage has been measured as 60 mV under the electrical load 4 Ω. It is believed that this optimized device can be more successful for engineering applications with an enhanced power.