An amp capacitor is a device that stores and holds electrical charges in order to smooth out variations in the electrical signal. Music is made of electrical waves that quickly change from plus (+) to minus (-) throughout the length of the song. A capacitor is made of plates (electrodes) that are separated by a material that can collect and hold electrical charge. As the signal changes from + to -, a portion of the charge is used (discharge). However, upon the signal changing back from – to +, the capacitor gains a portion of its charge (recharge). The capacitor does this continuously so long as it is connected into the circuit.
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