There’s a project I’m working on (yes ANOTHER one, stay tuned, I’m serious with this one!) where I need to use a motor with around 20rpm that runs on 3-5V DC. I actually [found one] but it’s awfully loud. I opened a gear Motor that runs on 230V AC to see, why that one is much more quiet (only vibration).
My guess is that the DC motor produces more noise due to its higher pulse frequency and the brush contacts whereas the AC motor has no brushes and pulses with 50Hz, a frequency not amplified by its enclosure…
Tags: Electronics