Whereas a typical window air conditioning unit is a solid metal box, the Midea U has a notch, roughly the width of a window, that runs the length of its body. As a result, half of the unit sits inside your living space while the other remains outside, with the two halves separated by your window. All the noisy components—the ones that in a standard AC would usually rattle away inside your bedroom in a symphony of growls and screeches—stay on the opposite side of your window, insulating your room from the sound. The Midea U is the quietest (and most energy-efficient) AC unit that Wirecutter has ever tested, and it’s the only air conditioner I haven’t wanted to turn off in the middle of the night.
