How noise cancelling headphones work
Noise cancelling headphones reduce external noise by cancelling out certain consistent frequencies they "listen" to in your environment with a microphone. They use that to cancel that sound with an off-setting out before it reaches your ear. There are technical explanations here but in genearl they work very well for things like jet engines, air conditioning, tire noise, vacuum cleaners and anything else that has a constant droning sound. Unfortunately noise canceling will do nothing to keep you from hearing the person in the cube next to your or your kids.
What are noise isolating headphones?
|Noise Isolating in ear|
Types of noise cancelling headphones and earbuds
|Bose In ear buds|
As mentioned there are closed back and in-ear noise cancelling. Both work equally as well. It depends on if which style you're more comfortable with. Personally over ear head phones with a few exceptions (higher end Sony headphones) will start hurting my ears after about an hour or two. If you have smaller ears this may not be a problem for you.
|Bose Closed Back over ear|
Closed back over ear headphones
Over ear noise cancelling headphones offer good isolation of external noise as well as comfort to those who prefer not to stick something in their ear canal. They also have the benefit of having the electronics that do the noise cancellation inside the headphone.
In ear, or ear bud noise cancelling headphones will fully block the ear canal offering some isolation in addition to electronic cancellation but have an small external box to house the electronics. For me this is worth it but you might find it annoying. Be very careful that what you're getting has active electronics and is not a noise isolating headphone purporting to have cancellation.
Which is better?
If you are trying to block out white noise type sounds like a jet engine then noise cancelling is the way to go. If you want to partially block our your coworkers than noise isolating works just as well. As for in ear or over ear it depends on which you're more comfortable with. If you usually wear over ear headphones then that's your best choice. If you prefer in ear headphones like I do, then that's the way to go.
Which do you perfer?