In-ear noise-canceling headphones by far isolate the most amount of outside noise anyone could ever hear. Even just passively, IEM’s can compete very well with the best noise-canceling cans (Bose to be specific) out there.
I feel odd about this headphone type (in somewhat the same way that I do for on-ear noise cancellers). I do think that because these types of ‘earphones’ already isolate excellently, there’s no need for the extra active-noise canceling features. It also makes the hefty price tag not so worth it considering there’s not much difference in terms of isolation when using the earphone’s active noise cancellation feature.
Enough on that rant, here are the top ones that I can see out there:
Sennheiser CXC700 – The CXC700 is included in Sennheiser’s newest lineup of noise-canceling headphones that have the NoiseGard 2.0. I do not have experience with this earphone (nor am I looking to get some) but I heard that it is a pretty good in-ear noise-canceling earphone. It’s not really saying a lot since earphones in this category are few and far between.
Just like other Sennheiser headphones of this type, you are not forced to use the active noise canceling feature. The problem is once you’re not using it, the volume level of the headphones on portable devices, while acceptable, is not that loud considering the high impedance rating of these earphones. But still, it’s a competitive product for this type (and if you’re willing to shell out some money). Sennheiser CXC 700 on Amazon.
Audio-Technica ATH ANC23 – Probably the best bang for your buck in-ear noise-canceling product available. It doesn’t quite do as good as the earphone above but for more than half the price, you should be fine with it. According to Audio Technica, it isolates background noise up to 90% although we all know that it’s probably not true.
Sound quality is slightly above average (as mostly the case for this type) and there are also some comfort and fitting issues with these earphones as reported. You may wanna consider those factors when choosing this IEM. Audio Technica ATH ANC23 on Amazon.