I spend a lot of time near chairlifts.
They really don't have an electric hum at all, the only noise is usually a small rattle and that really depends on the overall speed of the lift itself, the average speed for a high speed lift is about 12 MPH. I wouldn't be surprised if these lifts run slower than a ski lift. Lifts that aren't maintained sometimes have a little more noise like a squeal. If you're standing next to it, you'd hear it but it shouldn't carry through a wall. And they won't be running overnight while most people are in their rooms sleeping anyways.