Person turning on and testing microphone and speaking into it against black background.
Person tapping microphone and speaking is this thing on in slow motion then turning it off.
Music Producer turning knobs on MPC
Man turning control knob on amplifier
Hand turning temperature knob of heater
The driver adjusting the volume of a radio inside a car. Close up of a woman hand with yellow manicure turning volume control
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Close-up tilting shot of Asian female science laboratory worker in white coat looking into microscope and turning knob to adjust focus, while studying specimen
Young Asian woman in glasses and headphones speaking to her audience
Close up of a man turning a knob on a stove
Bride is speaking on the microphone
Smiling caucasian podcaster speaking into professional microphone. Podcast presenter guy telling a good news for subscribers. Young