The main function of Kojo Seiko Crystal H1P is to detect and suppress the component DC contained in the commercial AC power supply and suppress the growl of the transformer installed in the audio equipment. In the main circuit configuration, bridge diodes are placed on both power supply lines. By taking advantage of the forward voltage characteristic (Vf) of the diode, the conduction period of the diode changes according to the level of the DC, and the DC is suppressed. The larger the Vf of the diode, the higher the effect and this product use Shindengen’s reliable and proven product.