Noise-cancelling headphones regularly top lists of essential travel gadgets, but are they worth it? Pic: The New York Times
A little bit of silence is sometimes that’s all we want, whether it’s halfway through a 10-hour flight with a crying baby, or trying to sleep though the snoring from the hotel room next door, the promise of noise-canceling headphones is one that every traveler probably finds intriguing.

Yet are they worth it? These headphones are often expensive and for some people, they don’t live up to the hype.

How and when noise-canceling headphones work:

Noise-canceling headphones, also called active noise-canceling headphones, use electronic processing to analyze ambient sound and attempt to generate the “opposite” sound. The result is less noise overall.

Imagine ocean waves. There’s the high part, the crest, and the low part, the trough. If you combined the positive height of the crest and the negative depth of the trough, the result would be a flat sea. This is essentially what active noise-canceling headphones do. Add troughs to crests and crests to troughs. Except instead of seawater, it’s sound waves.

It’s not perfect. these headphones don’t “create” silence, nor are they able to eliminate noise. The absolute best noise-canceling headphones merely reduce noise, and work best with low-frequency droning sounds, making a loud hum a quieter hum. 

The roar on an airplane is a quieter roar on an airplane. They also don’t work well for all sounds. At higher frequencies, like the human vocal range and higher, the headphones do very little if anything at all. So if your hope is to block out the cries of the baby in seat 15C, you’re out of luck.
Fast and transient sounds, like a door slam or a hand clap, also aren’t blocked effectively.

Not all noise-canceling headphones work the same. The best reduce a lot of noise, the worst reduce very little or nothing at all. There’s no way to tell, looking at a headphone’s specs, which are which.

Noise-canceling headphones require a battery to power their electronics. Noise-isolating headphones, which do not require electronics and therefore can be far cheaper, work by creating a seal in your ear canal to block noise. 
Basically they are like earplugs, but with earbuds inside. If you can get a good seal, these work reasonably well.

Getting a good seal can be a challenge, however, since everyone’s ears are different and not all headphones will fit correctly. And even if you do get a good seal, noise-isolating headphones will not be able to block low-frequency sounds as well as the best noise-canceling headphones. They will reduce a wide range of frequencies, which can help.

Who really needs noise-canceling headphones?

If you are a frequent traveler, good noise-canceling headphones will make any journey in a plane, train or automobile far more pleasant. 

In-ear models are easier, though still slightly uncomfortable, to sleep with. Over-ear models reduce a little more noise as they are able to passively block some sound because of their design, but they are always bulky on your head or in your bag. 

However, if you rarely travel, or you find higher-frequency noises like people talking, cars hooting and noisy neighbours more annoying than airplane engine noise or background chatter, these headphones may not be worth it.
Cheap earplugs, or perhaps noise-isolating earbuds, might work well enough. 

Overall, noise-canceling headphones are great for frequent flyers, however, for non-frequent travelers, this product might not necessarily be the must-have travel accessory that it might seem.