\r\n\r\nThey've been hailed by ear doctors around the globe as the perfect solution to people's listening problems, but how do noise cancelling headphones work? Are they really as safe as we've been told? Once you feel comfortable with using noise-cancelling headphones, take a look at our I-MEGO walker jr noise-cancelling headphones review.\r\n\r\nSure, outside noise can often cause us to crank our source volume up past safe volumes in order to\u00a0hear our music, but\u00a0there's also growing concern that noise cancelling headphones may work just a little\u00a0too\u00a0well. \u00a0So well that people are\u00a0walking into traffic or being knocked down by bicyclists\u00a0due to not being able to hear what's around them.\r\n\r\nIn this guide we'll tell you everything you need to know about how the noise cancellation technology works, and what you should look out for if you plan on picking up a pair of best rated noise cancelling headphones\u00a0yourself.\r\nActive Cancellation vs. Passive\r\nFirst off, readers should note that when we talk about noise-cancelling headphones, there are actually two separate implementations of the technology at work: active, and passive.\r\n\r\nPassive Noise Cancelling: It's\u00a0achieved simply through designing either the earbud or the headphone cup to completely fill the ear canal or wrap around the user's ears in a way so no outside sound can find a way in.\r\n\r\n\r\n\r\nActive Noise Cancelling: The second (and generally more effective) method of noise-cancelling is called active cancelling, where a separate microphone is used to listen to\u00a0the ambient noise, and then the headphones use small speakers in the buds or cups\u00a0themselves that point outward to play an audio file that's inverse of the waveform coming in.\r\n\r\nThis technique creates a sound barrier around the wearer's ears that effectively "cancels" out the surrounding noise, although it's not still without its own problems.\r\nActive Doesn't Always Mean Better\r\nMost active systems rely on an external battery in order to power the onboard speakers, something that can add a bulky amount of weight to either the cord or the headphones themselves. Not only that, but active noise-cancelling headphones also have trouble keeping up with noises that aren't constant in wavelength.\r\n\r\n\r\n\r\nThis means although they're great for negating annoyances -\u00a0such as\u00a0the drone\u00a0of an airplane engine that stays at a low, persistent volume - when it comes to drowning out other people speaking around you (say in a noisy office), the active cancellation will struggle to compensate quickly enough and can let sound leak in.\r\n\r\nThat's where passive noise-cancelling buds or over-the-ear headphones might be preferable, as they can cut off inconsistent sounds. \u00a0Just keep in mind that you should exercise caution when wearing any headphones, as removing ambient sound reduces your awareness of your surroundings.\r\n\r\nNo matter which variety you end up going with, you can always check out our guide on the best noise cancelling headphones\u00a0and latest noise cancelling headphone reviews to\u00a0make the best possible pick for your active (or passive) lifestyle!