Do all headphones reduce exterior noise?
– Yes. However, those types that surround the ear (circum-aural) generally afford better noise reduction than other types.
– This is because the padding that surrounds the headphone elements forms a tight seal against your head. Also, keep in mind that the noise reduction figure often quoted by headphone manufacturers is an overall noise reduction value – some headphones will be better at reducing low frequency background noise, but not necessarily high frequency noise, and vice versa.
– Regrettably, most headphone manufacturers do not provide a plot of noise reduction versus frequency, but there are websites that test headphones this way