Originally Posted by
tommyleo
I've found that any noise canceling headphones, when used without music, actually make it easier for me to hear people speaking (and babies crying) while flying. Here's why: the headphones cancel constant noise -- such as jet engines. However, the headphones do nothing to cancel speech, so you will likely notice speech more with the headphones on since the engine noise is reduced so much. If you need to remove speech, crying, etc., try using ear plugs as well as the headphones. That should help a lot.
You're correct in your observation. One other reason for this: Noise-canceling phones work in the lower frequency ranges and have no effect in the range of human speech (and crying babies).