Impedance : pay attention to the meaning of the resistance distinction, in a direct current (DC) in the world, the function of objects in the current obstacles called resistance, but in an alternating current (AC) in the field is in addition to the resistance would block the current beyond, capacitance and inductance will prevent the flow of the current, this effect is called the circuit reactance, and our daily said Impedance is resistance and in the circuit reactance vector and.

What is the impedance headphones, earphones impedance is exchange impedance abbreviation, the smaller the impedance, the headset the easier to sound, the more likely to drive. In desktop or power amplifier, VCD, DVD and television have headphone jacks output of machine, use commonly be suitable for high impedance headphones. If use the low resistance headphones, we must first turn down the volume on the headset again, again a little bit turn down the volume up, prevent headset overload will burn out or headset voice coil deformation caused by dislocation hissing sound. Low impedance headset is compared commonly easy to push, so the walkman, MP3, portable, save electricity machine should choose low impedance headphones. At the same time pay attention to high sensitivity, the walkman, MP3 is more important sensitivity index. Of course, the higher the impedance of the output power of the big match headphones when audio source better sound.

Inductance and capacitance has resistance, the, on alternating current to obstruct called impedance. Impedance commonly used Z said. Impedance by resistance, inductance and RongKang three component, but not the three simple addition. If the three series is, and that the frequency of the alternating current f, resistance R, inductance and capacitance C L, then a series circuit impedance, the impedance of the unit is Europe.

For a specific circuit, impedance is not constant, but as frequency changes. In resistance and capacitance and inductance series circuit, the impedance of the circuit in general than resistance. Also is the impedance reduced to the minimum. In the inductance and capacitance in parallel connection circuit, the resonance when increased to maximum impedance, this and a series circuit instead.