Excerpt: Noise canceling headphones should, at a minimum, cancel noise. When you put these uncomfortable headphones on, they muffle some noise. When you turn on the noise reduction feature, if you pay very, very close attention, you will notice that a tiny bit more noise vanishes. It's easy to miss, though. I wore them for about an hour into the first leg of a flight, and finally ripped them off. They were hot and sticky, and kept me from falling asleep.