[Frank Herrmann] had an interesting idea to turn a geared DC motor into a servo motor ... provide all that is needed to read the encoder, control the motor rotation and listen on the ‘stepper ...

That’s because brushless DC motors require carefully timed signals used in a process called Electronic Speed Control (ESC). [Fileark] built and ESC using an Arduino and has a couple of posts ...

Speed control ... Full 4 quadrant control can be achieved with brushless motors using only hall sensors. A DC tacho or encoder can be optionally used with the DC motor for tighter feedback loops ...

Related to my search for reduced motor noise (and thanks to all who have made suggestions ... Imagine my joy when I came across Design notes on precision phase-locked speed control for DC motors, and ...