A capacitor is an electronic component that stores energy in an electric field.

Think of a capacitor as a tiny, rapidly discharging battery. It consists of two conductive plates separated by an insulating material (the dielectric). When a voltage is applied, it accumulates a positive charge on one plate and a negative charge on the other, storing energy.

The storage capacity of a capacitor is measured in Farads (F).

The most important characteristic of a capacitor in audio circuits is its behavior with alternating current (AC), which is how the audio signal is presented:

• Blocks Direct Current (DC): A capacitor does not allow direct current to pass through it.

• Allows Alternating Current (AC) to Pass: It acts as a kind of "resistance that decreases with increasing frequency". High-frequency signals pass through it more easily than low-frequency signals.

Because of this property, capacitors are essential components in audio circuits, being used for:

• Filters and Equalizers: To separate and control different frequency ranges.

• Signal Coupling (Coupling): To block the DC voltage of one stage of the circuit, allowing only the audio signal (AC) to pass to the next stage.

• Power Supplies: To filter and smooth the electrical current.