Rotary knobs are also known as what?

• A. Associated with color temperature control
• B. Also known as a bus or bus controller
• C. Used to adjust audio gain
• D. Used as a dimmer switch

Answer: (B)

This question tests terminology for control surfaces on audio/mixing gear. Rotary knobs on a mixer are used to set levels, including the levels sent to different signal paths called buses. In that context, those knobs are part of the bus control section, so they’re described as bus controls or bus controllers. The other options refer to different functions: color temperature control is a lighting setting, not a bus-level control; adjusting audio gain is a gain or trim control, not a bus control; and a dimmer switch is for lighting intensity, not routing signals through a bus. So the term that best fits the role of turning a knob to manage a signal path is bus or bus controller.