A potentiometer (commonly abbreviated to pot) is a variable resistor, arranged in a rotary manner (rather than a linear manner) to allow control over a value.

• On a Sound Desk or Mixing Desk pots are used for numerous adjustments such as gain, equalisation, auxiliary sends and pan on a channel. The resistance law of the pot is logarithmic to reflect the human ear's response to loudness of sounds.

• On a Lighting Desk pots are usually used to set fade times or chase speeds. The resistance law of the pot is usually linear, although the software in the desk may process this to provide an exponential type response, particularly for fade times, where the exact time is generally less critical for longer fades.

Pots may have a click-off, or centre detent, to provide tactile feedback about the setting.

The cap is usually a separate part, which is either simply pushed on, held in place with a small grub screw, or attached by a nut hidden under the cap cover.

Internal adjustments inside products use pots, although generally no cap is fitted and a small adjustment screwdriver is required.

See Also

• Fader

• Discussion