Filter capacitor
A large capacitor in the power supply that stores energy and smooths the direct current delivered to the amplifier's circuit.
Filter capacitors are the reservoir that supplies current during loud transients, when the transformer alone cannot keep up, which is why their condition and size affect both the feel and the noise of an amplifier. Ageing electrolytic capacitors dry out, losing capacitance and eventually leaking or failing, and a re-capped amplifier often sounds tighter and quieter than the same unit did before. Because they hold a lethal charge even when the amplifier is switched off, they are the one part of an amplifier that no untrained person should touch.
Example: An amplifier that hums increasingly with age, especially at idle, may need its filter capacitors replaced.
See also
Related
- PagePower transformer
- PageChoke
- PageHum
- PageAmp in a box
- PageAmp stand
- PageAttenuator
- PageAaron Dessner
- PageAce Frehley