trimmer

Note the two trimmer screwdriver slots, surrounded by blue, in the middle of this phase shifter.

Aisha Loe explains how to cure mushy modulation with a screwdriver—but you need to know what you’re doing.

Potentiometers are used for most of the controls on pedals and a lot of other electronic equipment as well. A potentiometer (also known as a pot) is defined as a 3-terminal variable resistor in which the resistance is manually varied to control the flow of electrical current. A potentiometer acts as an adjustable voltage divider. Any control on a guitar pedal that has a knob will typically be controlling a potentiometer, or sometimes a rotary switch.

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