Sound, Radio & InformationWave Interference
Silence Made of Sound
Noise-canceling headphones add sound to make quiet
Some headphones hush a jet's roar at the flip of a switch, and they do it by playing more sound. How can that work?
You'll find out
- When two sounds add up to nothing
- What hides inside each ear cup
- Why voices still get through
Why it matters
Waves that cancel explain quiet cabins, calmer cars and why some sounds always slip past your headphones.
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