Q: I see a lot of keyboards and control surfaces that say they have “encoders.” Isn’t this just a regular knob?

A: A rotary encoder does indeed closely resemble (and perform) like a traditional control “knob” on a mixer, keyboard, or other electronic device. The difference is that a rotary encoder sends digital data as it is turned, which is then used to affect a parameter setting. A traditional “knob” may directly affect an analog signal or may be used to regulate voltage that is being used to control a parameter.

The other difference is that most rotary encoders can be assigned to whatever parameter is desired, while a traditional “knob” is typically locked to one control function.