How Noise-Canceling Headphones Create Silence in Microseconds | WSJ Tech Behind?

Noise-canceling headphones make loud sounds quiet really fast, like turning down a noisy toy before it can bother you.

Sound waves are like invisible ripples in the air. When you're in a busy room, lots of these ripples come at your ears all at once, that's why it feels so noisy.

Now imagine your headphones have tiny microphones inside them, like little listening toys. These microphones hear what’s going on around you and send that information to a smart brain inside the headphones.

This smart brain quickly figures out how to copy the sound waves but in reverse, like playing back a song backwards. Then it sends this reversed copy through speakers right next to your ears, just milliseconds later.

When these two sounds meet, the real noise and the copied one, they cancel each other out, like when you and a friend both jump on a trampoline at the same time, and the bounce becomes smaller. That's how your headphones can turn loud noises into quiet ones in microseconds, faster than you can blink! Noise-canceling headphones make loud sounds quiet really fast, like turning down a noisy toy before it can bother you.

Sound waves are like invisible ripples in the air. When you're in a busy room, lots of these ripples come at your ears all at once, that's why it feels so noisy.

Now imagine your headphones have tiny microphones inside them, like little listening toys. These microphones hear what’s going on around you and send that information to a smart brain inside the headphones.

This smart brain quickly figures out how to copy the sound waves but in reverse, like playing back a song backwards. Then it sends this reversed copy through speakers right next to your ears, just milliseconds later.

When these two sounds meet, the real noise and the copied one, they cancel each other out, like when you and a friend both jump on a trampoline at the same time, and the bounce becomes smaller. That's how your headphones can turn loud noises into quiet ones in microseconds, faster than you can blink!